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i 



I* 



MARINE ENGINEERS' 
HANDBOOK 




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PUBLISHERS OP feOOKS FOR«^ 

Coal Age ^ Electric Railway Journal 
Electrical \U3rkl ^ Engineering News-Record 
American Machinist v Jqgenierfa tntemacional 
Engineering 8 Mining Journal ^ Power 
Chemical 6 Metallurgical Engineering 
Electrical Merchandising 





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Marine Engineers' 

Handbook 



PREPARED 
BY A STAFF OF SPECIALISTS 



FRAXK WARD STERLING, Editor-in-Chief 

UBI7TBKA3VT COMllANDEB, U. B. NAVY, DEBIQN DIVISION, BT7IUEAU 
or STSAM KNGXNBBRINO, NAVY DEPARTMKNT; BEC'y. AND TBEA8. 
A. 8. K. K.; UKMBEB SOCIETY NAV. ARCH. AND MAB. BNO. 



First Edition 



McGRAW-HILL BOOK COMPANY, Inc, 

NEW YORK: 239 WEST 39TH STREET 
LONDON: 6 ft 8 BOUVERIE ST., E. C. 4 

1920 



Thb Editob-iiI-Ohisif akd tse Pttbubhebs will BB QBAISrUL TO RBAoeai 
WHO Notify thbm or any Inaocubacy ob Impobtant Omibsion in this Bool 



CoPYBiGHT, 1920, Bt THB McGkaw-Hill Book Company, Inc. 



All Riobts Rbbbbved, Includino Thobb of Tbanblation 



Tax MAPI.X PH1B8B TOHK PA 



^^ 

^ LIST OF CONTRIBUTORS 

Bdward M. Bra^g, B. S., Professor of Naval Arohitecture and Marine 
Eneineermg, University of Michigan; Mjdm. Soc. Nav. Aroh. & Mar. 
£ng. and A.S.N.E. 

John Shober BiiztoW8, Consulting Engineer for Castner, Curran A Bullitt; 
Mem. U. S. Fuel Administration, U.. S. Geological Survey, U. S. Govern- 
ment Coal Testing Plant; Mem. A.S.T.M., Inter. Ry. Fuel Assn^ 

A. 6. Christie, M. E., University of Toronto; Asso. Professor Mechanical 
Engineering, The Johns Hopkins University; Mem. A.S.M.E., Amer. 
Gas. Afiso. 

OuiUiam Henry Clamer, B. S., First Vice-President and Secretary, The 
Ajax Metal Company, Pres. Am. Inst, of Metals, Mem. Brit. Inst, of 
Metals, A.S.T.M., Am. Chem. Soc., Brit. Iron & Steel Inst., Etc. 

J. A. Daries, Ass*t Gen. Supt., Essington Wks., Westinghouse Electric & 
Machine Co.; Mem. Soo. Nav. Arch., & Mar. Eng. & A.S.N.E. 

John H. Deppeler, M. £., C'hief Engineer Thermit Dept., and Supt. of Ther- 
mit Plants, Metal and Thermit Corp., Mem. A.S.M.E. 

Wajne T. Dimm, B. S., Assistant Chief Engineer, Newport News Ship- 
building and Dry Dock Company; Mem. A.S.N.E. and Soc. Nav. Arch. 
A Mar. Eng. 

Charles W. Dyson, Rear Admiral U. S. Navy, Head of Design Division, 
Bureau of Steam Engineering; Navy Department, President, A.S.N.E. 

H. &. Qary, Manager, Cummings Ship Instrument Works, Mem. Soc. 
Nav. Arch. A Mar. Eng. and A.S.N.E. 

frank Qentles, Ass't Chief Engineer, Div. C. & R.W.S.. Shipping Board, 
Emergency Fleet Corp.; Asso. Mem. A.S.M.E. and Mem. Soc. of Nav. 
Arch. & Mar. Eng. 

O. A. Qoodenough, M. E., Professor of Thermodynamics, University of 
niinois. 

r. O. Heckler, M. S., Naval Experiment Station. 

H. A. Homer, B. A., Vice-President Illuminating Engineering Society ; 
Follow, A.I.E.B., Past Chairman, Marine Committee, A.I.E.E.; Mem. 
Franklin Institute, Am. Electro-Chemical Soc, Amer. Soc. for the 
Advancement of Science, Physics Club of Phila., A.S.N.E. 

Snsaell C. Jones, M. E., Vice-President Griscom-Russell Co.; Mem. Soc. 
Nav. Arch. & Mar. Eng. and Asso. Mem. A.S.N.E. 

Martin L. Xatzensteln, Manager Marine Dept., Worthington Pump and 
Maehineiy Corp., Mem. A.S.M.E., Soc. Nav. Arch. & Mar. Eng., and 
A-S.N.E. 

Baines Kessler, American Engineering Company, Mem. A.S.M.E., A,I.E.E. 
and A.S.N.E. 

V 



vi LIST OF CONTRIBUTORS 

O. I. L. Kothny, M. E., Consult. Eng. & Manager Marine Dept., C. H. 
Wheeler Mfg. Co., Mem. Soc. Nav, Arch. A Mar. Eng., A.S.M.E., 
Franklin Inst., Asso. Mem. A.S.N.E. 

Louis Lanjrl, Chief Engineer, Steem-0-Lite Co., Mem. A.S.M.E.. 

D. J. McAdam, Jr., M. S., Ph. D.. Metallurgist, U. S. Naval Experiment 
Station, Annapolis, Md., Mem., A.S.N.E. 

P. NichoUs, Technical Section, The Franklin Mfg. Co. 

Ernest H. Peabody, M. E., Stevens Institute of Technology, President, 
Peabody Engineering Corp., Mem. Soc. Nav. Arch. & Mar. Eng., 
A.S.M.E., A.S.N. E., Soc. Liquid Fuel Engineers, Nat. Fire Protection 
Ass'n. 

Albert M. Penn, Lieutenant Commander U. S. Navy. In charge of Navy 
Fuel Oil Testing Plant; Mem. A.S.N.E. 

Stuart Pluznley, Engineer-in-Chief, Engineering and Research Depart- 
ment, Davis-Boumonville Co. 

Joseph H. Price, B. S., Chief Engineer, Griscom-Russell Co., Assoc. Mem. 
A.S.N.E. 



Rotter, Vice-President in charge of Engineering of the Busch-Sulzer 
Bros. Diesel Engine Co., Mem. A.S.M.E. and A.S.N.E. 

O. B. Rowland, Supervising Engineer. The Texas Co., Mem. A.S.M.E., 
S.A.E., A.S.A. and N.A.S.E. 

Max SpiUman, B. S., Works Eng., Henry R. Worthington; Mem. A.S.M.E. 

Vtaak Ward Sterlinir* Lieutenant Commander, U. S. Navy, Design Division, 
Bureau of Steam Engineering, Navy Department; Sec'y-Treas. A.S.N.E.; 
Mem. Soc. Nav. Arch, A Mar. Eng. 

Iffayson W. Torbet, Captain of Engrs., U.S.C.G., B. Mar. E., Mem. 
Council, A.S.N.E. 

Karl D. Williams, Ph. B., Metallurgical Engineer, Inspection Division, 
Bureau of Steam Engineering, Navy Department, Mem. A.A.E., 
A.S.N.E. 



PREFACE 

This handbook is compiled for the use of operating and designing engineers 
and of students. To cover the main subjects and the many ramifications of 
jDsrine engineering it has been necessary to enlist the services of thirty 
specialists. Each specialist in turn has received the hearty cooperation 
of others in the same field. The best endeavor to coordinate the different 
pnctiees has been put forth in order that all data may be reliable and unbiased. 

Marine engineering differs from mechanical engineering in its state of 
jdevdopment. While mechanical engineering practice is standardised in 
inast of its branches, marine engineering is in a stage of transition. But one 
type of prime mover, the reciprocating engine, can be said to have reached 
Its final development. Such being the case, and considering that many mat- 
ten of design practice are jealously guarded as trade secrets, the task set for 
the GontributoTB to this book has been severe. Combine this with the fact 
that much of the work represented herein was performed during War times 
when but little leisure was available, and the reader will understand the deep 
obligation that the Editor-in-Chief feels toward the authors of the various 
sections. A patriotic pride in aiding our growing merchant marine has been 
a controlling factor with many of them. 

, All the large shipyards have contributed to this work. In every instance 
jcredit has been given in the text. Hundreds of marine manufacturing com- 
panies have furnished data. The list is too large to attempt here but the 
feeder will meet our friends on every page. 

Many friends in the Bureau of Steam Engineering, Navy Department, 
kave given valuable aid in searching records and checking data. The U. S. 
Naval Experiment Station at Annapolis, Md., furnished and checked much 
test daU. The U. 8. Naval Fuel Oil Testing Plant has made possible the 
very complete section on Oil Fuel Burning. The Journal of the American 
Society of Naval Engineers has furnished much useful material. 

Professor Lionel S. Marks, the Editor-in-Chief of the Mechanical Engi- 
neers* Handbook, has allowed a most generous use of material from his classical 
work and has contributed much kindly and useful advice in the early stages 
of this undertaking. 

The £>litor-in-Chief wishes to express thanks to the publishers for assist- 
ftooe at many stages of this work, in obtaining material and contributors, but 
BioBt of all for their courteous patience in the face of the many unavoidable 
itisyi throughout. 

Finally, the reader must bear in mind that this handbook is a pioneer in 
its field. The trail has not always been plain to read. This edition aims at 
1 BBoeral survey of the new territory. The lack of standardisation in Marine 
•ng inc e r ing has made its presentation in handbook form somewhat difficult. 

FRANK W. STERLING. 

CAUTION 

^laoy of the structureB and proceasea herein described are protected by U. S. and 
rarciSB patents. H would tmneoessarily lengthen the text to state this fact with refer- 
•nee to each case to which it wouM apply; hut designers and users are cautioned against 
■tiisin^ stmoturee or processes without previously assuring themselves that such uae is 
aot sabject to patent restriotiona. 

vii 



CONTENTS 

(For Alphfltbetica] Index, see p. 1450) 



SECTION 1 



MATHBMATICAI. TABLB8 AND rOBMUL. 

AND 
BIBCHANICS OF BiaiD BODIS8 



lbth«inatle»l Tables and Tormul» 

Pack 

Goounon Logaiithnie 2 

TkicBometric Functions 6 

I^KiniAl Equivalents 11 

Csdes (CircumfereDces and Areas) . 12 
CooTcraion Tablee: 

Acceleration of Gravity 14 

Fortea 14 

Leogtfaa 15 

Area 15 

Vohimea and Capacities 16 

Velocitiee 16 

Mattes 17 

Ptcasttres 17 

Bneriy, Work, Heat 18 



Paos 

Power 18 

Density. 19 

Heat Transmission and Conduc- 
tion 19 

Trisonometric Formule 20 

Dinerential Formulie 22 

Indefinite Integrals 23 

Definite Integrals 26 

Mechanics of Rlffld Bodies 

Definitions 27* 

Unite 27 

Kinematics 29 

Statics 32 

Kinetics 38 



SECTION 2 

HON-FEBBOUS AND FBBBOITB MXTAL8 

AND 



Hon-torrous Metals and Alloys 



Pore Metals. 
BroiuRs 



ftwiRth of Metals and Alloys at 

ffifh Temperatures 

Bearina Metals 



Page 

41 
53 
56 



oeanng 
Whiteli 



68 

68 

fetal Alloys 78 



Iron and Btoel 



^ of Iron 79 

gtiBction of Iron from Ore. 80 

Hstt Furnace Products 81 

UeUOocraphy 82 



Paob 

Chemistry of the Purification Pro- 

cessee 87 

Wrought Iron 88 

Steel 89 

Ingoto 97 

Mechanical Treatment 98 

Heat Treatment 98 

Influence of Chemical Compoaition 

on Physical Properties 103 

Case Carburisation or Partial 

Cementation 109 

Caet Iron Ill 

Perro Alloys 119 

Specifications for Wrought Iron. . . . 121 

Specifications for Steel 122 

Specifications for Cast Iron 148 

Protective Coatings for Iron and 

Steel 168 



IX 



CONTENTS 



Bcrew Threads, Bolts and Nuts 

Page 

Screw Threads 168 

Bolts aod Nuts 161 



Ozy-acetflens Welding 

Gases for Welding and Cutting 163 

Burners 164 

Expansion and Contraction 165 

Welding Rods 166 

Fluxes 167 

Welding 168 

Cutting. 171 

The Thermit Weldinc Process 

Composition 172 

Kinds of Thermit 172 

Physical Properties 173 

Large Welds 173 

Crank Shaft Repairs 176 

Pipe Welds 176 



Beat 

Pagi 

Temperature Measurement 177 

Expansion ITS 

Specific Heat 180 

Freesing Mixtures 183 

Melting Points of Solids 183 

Freesing and Boiling Points 18S 

Heat of Fusion and l^atent Heat. . . ISl 

Transmission of Heat 18i 

Thermal Conductivitiee ill 

Thermodynamies 19S 

Perfect Gases 2O0 

Gas Mixtures 201 

Expansion of Gases 226 

Ideal Cycles with Perfect Gases 201 

Air Compression 203 

Vapors, Properties of 203 

Steam Tables 203 

Refrigerants 243 

Expansion of Vapors 247 

Mixture of Gases and Vapor 223 

The Steam Engine 226 

Refrigeration 228 

Flow of Gases and Vapors 227 

Throttling 237 



SECTION 3 



rUBL8 AND COMBUSTION 
OIL rUKL BUBNING 



Goal 

Page 

Composition 241 

Analysis 241-243 

Classification. 243 

Marine Coals 243 

Selection and Inspection of Coal for 

Marine Use 245 

Spontaneous Combustion and Stor- 

ajyo 245 

U. S. Navy Coal! '.V.'.'.'.V.V.V.V.V. 246 

Standard Steaming 247 

Sampling 247 

OUFuel 

Petroleum and Fuel Oil 250 

Properties of Petroleum 261 

Costo. Coal and Oil Fuel 262 

Oil Fueling Stations 263 

Advantages, Coal and Oil Fuel 264 

Phsrsical l^operties 266 

Heating Value 266 

Viscosity 266 

Viscosity Conversion Curves 260 

fitoecific Gravity 262 

Expansion 262 

Specific Heat 267 

Flash Point 268 

Fire Point 269 

Centrifuge 271 

Conservation. 273 



Paoi 

Safety Precautions: 

Burning 274 

Carrying 275 

Loading 276 

Commeroial Gasoline 

Prop«rtie8 277 

Specifications 277 

Tests 278 

Combustion 

Air Required for 279 

Excess Air 280 

Volume Contraction 280 

Combustion Products 280 

Oil Fuel Buminir 

Atoroization and Atomisers 281 

Air for Combustion 287 

Air Registers 293 

Boiler Furnace Design 297 

Furnace Insulation 297 

Relations Between Rate of Com- 
bustion, Heating Surface, Furnace 

Volume and Air Pressure 209 

Fuel Oil Equioment 301 

Boiler Room Instruments 315 

Operation 322 

Precautions 328 



CONTENTS 



XI 



SECTION 4 
MABIHB BOILERS 



Paoe 

DBTdopment 333 

DeMCnakion 330 

UmT Requiremente 343 

QenermI Dmi^ 343 

£Sect OD Desigix of 

Fnd 344 

Drmft 344 

Stcmm Preaeure 352 

Steam Output 354 

Sue and Number of Units 357 

Bpaee and Wdght 358 

Boiler Sues and Weighta 358 

Deaign of Scotch BoUera 385 

Rales and ReguLitioDs Governing 

Boiler Construction 390 

Factor of Safety 391 

Hydraufic Testa 392 

Hivtfted Joint!} 393 

Calkinc 405 

Welded Drums 406 

Bumped or Dished HracU 406 

Manholes and Handholcs 408 

Qrfindrica] Shells. Rivetpd 408 

Flat Surface Stayed 410 

Stays 413 

Fomaees 415 

Combtistion Chambers Girders. . . 120 



Paqk 

Combustion Chamber Tube Sheet. . 421 
Cylindrical Tube Sheets, Water 

Tube BoUer Shells 422 

Diagonal Ligaments 422 

Scotch Boiler Construction 426 

Tubes 434 

Boiler Setting 438 

Boiler Mounting 440 

Furnaoe Mountings 453 

Superheaters 461 

Care of Boilers 

Preservation of Idle Boilers 464 

Prevention of Exterior Corrosion 464 

Raising Steam 464 

Removal of Oil 465 

Internal Corrosion 466 

Boiler Repairs 475 

Fuellftud Firing 477 

Time Firing 478 

Cleaning F^es 470 

Air Required for Combustion 480 

Analysis of Gases of Combustion. . . 481 

Removal of Scale 487 

Boiler Tests 488 

Boiler Materials, Inspection Re- 
quirements 514 



. SECTION 5 



TUBBINB8 

AND 

MXCHAinCAL BIDUCTIOM QXARB 



Turblnas 

Paob 

of Steam 528 

Adiabatic Expansion 529 

Actual Expansion 533 

Nosalea 638 

Lnpulae Blading 543 

Cartas Blading 546 

PknoiM Blading 548 

Ckaranoes and Leakage 555 

Rotational Losses 561 

ftoviaaonal Proportions of Turbine: 

Wheel Efficiencies 563 

The limiting Factors, of Capacity 563 
Prorisaonal Proportions of an 

Impulse Turbine 664 

Fhyvisional Proportions of a 

Parsons Turbine 566 

Gaging 670 

ntrrisional Proportions of Direet- 

eoupled Parsons Marine 572 

IVoviaional Proportions of Astern 

Turbines 672 

^ovisional Proportions of Curtis- 

Rateau Turbuies 572 



Pa OK 



Turbine Desun: 
Design of a Simple Impulse 

Turbine 573 

Design of a EKmple Curtis 

Turbine 575 

Design of a Rateau Turbine 677 

Design of a Curtts-Rateau Tur- 
bine 580 

Design of a Parsons Turbine 581 

Design of a Curtis-Parsons Tur- 
bine 588 

Miscellaneous Thermodynamic Con- 
siderations 589 

Martin's "New Theory of the 

Steam Turbine'* 590 

Mechanical Design: 

Design of Turbine Discs 593 

Critical Si>eed of Rotors 605 

Design of Rotor Shafts 609 

Drum Rotors 609 

Shaft Couplings 609 

Blading 611 

Cylinder Construction 624 

Turbine Drains 628 



xu 



CONTESTS 



Page 

Dummy Pistons, Glands. Laby- 
rinths 631 

Casing Glands 633 

Bearings 635 

Balancing of Rotors 640 

Miscellaneous Mochanical Equip- 
ment 646 

Micrometer Gear 649 

Bridge Gages 650 

Governors and Valve Gears 653 

Lubrication System: 

Bearings 661 

Lubricating Oils 662 

Types of Lubricating Systems. . . . 663 

CW Pumps 667 

Strainers 669 

Oil Filters 671 

Oil Coolers 677 

Tanks 678 

Oil Piping 679 

Piping Ckinneetions: 

Steam Lines 679 

Traps and Drains 681 

Gland Piping 682 

Foundations 683 

Lifting Gear 687 

Mechanical Reduction Gearing 692 

Electrical Gearing 692 

U. S. S. Jupiter 693 

U. 8. S. New Mexico 694 

U. S. S. Tennessee 701 

S. 8. MjAloer 703 



Page 

S. S. Wulsty Castle 704 

Hydraulic Gearing 707 

Performance: 

Effects of Variation in Operating 

Conditions 710 

Turbine Testing 712 

Tests Data and Trials 715 

Trial Performance of U. S. S. 

Wadsworth 720 

Electric Drive Performance 720 

Performance of Small Steam 

Turbines 722 

Comparison of Marine Steam 
Turbines and Other Prime 

Movers 723 

Types of American Steam Turbines 732 

Weetinghouse Marine Turbines.. . 732 

General Electric Turbines 745 

De Laval Steam Turbines 755 

Kerr Turbines 762 

Poole Marine Turbines 767 

Direct Drive Marine Propelling 

Turbines 774 

The Ljungstrom Turbine 779 

Sturtevant Turbines 7S4 

Terry Steam Turbines 788 

Engine Room Lavouts 794 

Mechanioai Beduction Ctoars 

Types 806 

Pmion 808 

Gear Wheels 813 

Testing 815 

Care and Operation 815 



SECTION 6 



RXCIPBOCATIKQ ENOINK8 



Paok 

Classification, Developiumt 821 

Efficiency 

Thermal 827 

Mechanical < 830 

Determining Sise of the Engine. ... 831 

Proportioning of Engine Parts 837 

Cylinders 840 

Framing and Beds 850 

Reciprocating Parts 855 

Bearings 864 

Shafting 871 

Valve Gear 877 

Reversing Gear 899 



Pauk 

Turning Gear 004 

Attached Pumpe 006 

Piping and Fittings Oil 

Drafting Room Method of Laying 

Down the Engine 918 

Balancing 920 

Analytical Method 021 

Graphical Method 926 

Means of Improving Balance 032 

Turning Effort 034 

Weights and Dimensions 938 

Machining and Tolerances 039 



CONTENTS 



XUl 



SECTION 7 



MABIHX DIB8BI. XHOnnBS 



Pacus 

dflMfication 945 

Tlie Dkoel Endue: 

Opeimtio^ Prooeoees ^. . . 947 

PrMBura '. . . 948 

Ratio of Detivered to Imtieatod 

pQW«r 948 

Interoal Power Consiunption .... 949 

Foci Supply and Injeetioa 949 

SeavenciBg 950 



Pagb 

Lubrioation 050 

Cooling 950 

Fuel Consumption 951 

Overload Capacity 954 

Lubricating Oil Consumption. . . . 054 

Four Cycle vs. Two Cycle 954 

Steam vs. Diesel 950 

Types of Diesel Engines 057 

Semi-Diesel Engines 962 

Fuel Oils .• 963 



8ECTIOX 8 



VACUUM AND CONDEN8XR8 



Page 

967 
969 
970 



Vieiiam Messorement , 

Liaita of Vacuum 

ThCTmodynamlca 

Coodenaers: 

Main Surfaro Condensers 975 

Swfaee Condenser Design 976 

Scoop Condensers 982 

Keei Condensers 983 

AoxiBary Condensers 980 

MCondeoaen 983 



Paqb 

Jet Condenser Design 087 

Circulating Pumps 088 

Air Pumps: 

Wet Air Pumps 991 

Dry Air Pumps 092 

Wet and Dry Air PumpH 997 

Vacuum Augmenters 1000 

Condensate Pumps 1000 

Accessories 1001 

Arrangement of Condensing Plants. 1006 



SECTION 9 

8HZF rOBMS AND POWXUNO 

AND 
8CBXW PBOPXLUEBS 



Ships Forms ftnd Powering 
Ships P«nas 

PAtilC 

Choice of Dimensious 1013 

Uagth 1013 

areadth 1013 

Draft and Depth 1014 

Seoaomlcal Speed 1014 

Prismatic Coefficient 1014 

Oarre of Sectional Areas 1014 

PteaOel Middle Body 1018 

Vertical Priamatic Coefficient 1021 

Height t>f Metacenter .,. 1021 

Load Water Line 1022 

Body Plan 1022 

SimpUfled Porms 

MeEntee'a Form 1023 

Wlottleaey's Form 1023 



Powariof of Ship« 

Paob 

Steven's Formula 1025 

Effective Horsepower from Modnl 
Tests 1026 



Screw Propallan 



1028 



Thrust Deduction and Wake Gain. 
Slip Block Coefficients: 

Wing Screws 1030 

Singfe Screw Ships 1031 

Tunnel Boate 1031 

Deter minntion of Thrust De<luct> 

tion Factor 1032 

Mean Relative Tip Clearance 1033 

Resistance of Hull Appendages 1034 

Basic Condition for Analysis and 

Design 1035 

Cavitation 1043 

Analysis and Design of Propellers. . 1046 

Design of the Propeller 1055 

Forms for Computation 1056 

Standard Propeller Hubs 1062 



xu 



CONTENTS 



Paob 

Dummy Pistons, Glands, Laby- 
rinths 631 

Casins Glands 638 

BearinsB 635 

Balancing of Rotors 640 

MiaoellaneouB Mochanical Equip- 
ment 646 

Micrometer Gear. 649 

Bridge Gages 650 

Governors and Valve Gears 653 

Lubrication System: 

Bearings 661 

Lubricating Oils 662 

Types of Lubricating Systems 668 

Oa Pumps 667 

Strainers 669 

Oil Filters 671 

Oil Coolers 677 

Tanks 678 

QU Piping 679 

Ffmng Connections: 

Steam Lines 679 

Traps and Drains 681 

Gland Piping 682 

Foundations 683 

Lifting Gear 687 

Mechanical Reduction Gearing 692 

Electrical Gearing 692 

U. S. S. Jupiter 693 

U. S. S. New Mexico 694 

U. S. S. Tennessee 701 

a S. Mjdlner 703 



Page 

S. S. Wulsty Castle 704 

Hydraulic Gearing 707 

Performance: 

Eflfects of Variation in Operating 

Conditions 710 

Turbine Testing 712 

Tests Data and Trials 716 

Trial Performance of U. S. S. 

Wadflworth 720 

Electric Drive Performance 7JM> 

Performance of Small Steam 

Turbines 722 

Comparison of Marine Steam 
Turbines and Other Prime 

Movers 723 

Tsrpes of American Steam Turbines 732 

Westinghouse Marine Turbines.. . 732 

General Electric Turbines 745 

De Laval Steam Turbines 755 

Kerr Turbines 762 

Poole Marine Turbines 767 

Direct Drive Marine Propelling 

Turbines 774 

The Ljungstrom Turbine 770 

Sturtovant Turbines 784 

Terry Steain Turbines 788 

Engine Room Layouts 794 

Mechanical BeducUon Oears 

Types 806 

Puuon 808 

Gear Wheels 813 

Testing 815 

Care and Operation 815 



SECTION 6 



RXCIPROCATIKG KNGINES 



Pauk 

Classification, Development 821 

Efficiency 

Thermal 827 

Mechanical 830 

Determining Siae of the Engine. ... 831 

Proportioning of Engine Parts 837 

Cylinders 840 

Framing and Beds 850 

Reciprocating Parts 855 

Bearings 864 

Shafting 871 

Valve Gear 877 

Reverung Gear 899 



Paujh 

Turning Gear 904 

Attached Pumps 900 

Pipitig and Fittings 911 

Drafting Room Method of LayiuK 

Down the Engine 918 

Balancing 920 

Analytical Method 921 

Graphical Method 926 

Means of Improving Balance 932 

Turning Effort 934 

Weights and Dimensions 93S 

Machining and Tolerances 939 



CONTENTS 



xm 



SECTION 7 



KABiNX DIX8XL juraims 



Paob 

Claaaification 945 

The Diemsl En«iJie: 

Operating Prooeeaes ,. . . 947 

Preesune '. . . 948 

Ratio of Delivered to Indicated 

Power 948 

Internal Power Consumption .... 949 

Pud Supply and Injection 949 

Soavengins 950 



Paok 

Lubrication 050 

Cooling 950 

Fuel Consumption 951 

Overload Capacity 954 

Lubricating Oil Consumption. . . . 954 

Four Cycle vs. Two Cycle 954 

Steam vs. Diesel 956 

Types of Diesel Engines 957 

Semi-Diesel Engines 962 

Fuel Oils .• 963 



SECTION 8 



▼▲COTTBI AND 

Paoh: 

Vaeuam Meaaurement 967 

Liokits of Vacuum 969 

Thcrmodynanuos. 970 

Condensers: 

Main Surface Condensers 976 

Surface Condenser Design 976 

Scoop Condensers 982 

Keel Condensers 983 

Auzifiary Condensers 980 

Jet CondeosexB 983 



CONDENSERS 

Paob 

Jet Condenser Design 987 

Circulating Pumps 988 

Air Pumps: 

Wet Aor Pumps 991 

Dry Air Pumps 992 

Wet and Dry Air PumpH 997 

Vacuum Augmenters 1000 

Condensate Pumps 1000 

Accessories 1001 

Arrangement of Condensing Plants. 1006 



SECTION 9 

SHIF FORMS AND POWE&INO 

AND 
SCREW PROPEUBRS 



Shipg Forms and Powering 
BhiiM VonnB 

Paue 

Choice of Dimensions 1013 

Length ; 1013 

Breadth 1013 

Draft and Depth 1014 

Economical Speed 1014 

Prismatic Coefficient 1014 

Curve of Sectional Areas 1014 

Parallel Middle Body 1018 

Vertical Prismatic Coefficient 1021 

Height of Metaoenter 1021 

Load Water Line 1022 

Body Plan 1022 

Simplilled Forma 

McEntee's Form 1023 

Whittlesey's Form 1023 



Powflriag ol Blxipg 

Paob 

Steven's Formula 1025 

Effective Horsepower from Modnl 
Tests 1026 



Scraw Propellara 



1028 



Thrust Deduction and Wake Gain . . 
Slip Block Coefficients: 

Wing Screws 1030 

Single Screw Ships 1031 

Tunnel Boats 1031 

Determinntion of Thrust Deduct- 

tion Factor 1032 

Mean Relative Tip Clearance 1033 

Resistance of Hull Appendages 1034 

Bamc Condition for Analysis and 

Design 1035 

CaviUtion 1043 

Analysis and Design of Propellers . . 1046 

Design of the PVopeller 1065 

Forms for Computation 1056 

Standard Propeller Hube 1062 



XIV 



CONTENTS 



SECTION 10 



AVznjijtT MACBnrasr 



BTApoTAtora And Distillcn 

Page 

Evaporatoni: 

lyfarine Service 1070 

Types of Plants 1079 

Capacity. Space, Weight 1080 

Types of Evaporators 1080 

Material« of Construction 1081 

Accessories 1085 

Methods of Installation. . . '. 1086 

Rei^nerative Compressor 1091 

Piping Arrangenient 1093 

Operation 1094 

Distillers: 

Marine Service 1096 

Commeroial Types 1097 

Evaporator Feed Heaters 1098 

Feed Water Heaterg 

Types and Materials 1108 

Installation 1 104 

Sise Required 1107 

Design 1108 

Operation UIO 

Oil Coolers 

Design 1111 

Commercial Types 1113 

Operation • 1114 

Centrifugal Pumpa 

Characterlstie Curvw 1115 

Construction 1117 

Methods of Driving 1123 

Circulating Pumps 1 123 

Boiler Feed Pumps 1127 

Bedprocatinc Pumps 

Types 1 131 

Construction 1133 

Commercial Specifications 1133 

Tables of Commercial Siscs 1134 

Cargo Oil Pumps }}49 

Performance Factors 1151 



Paoe 

Design Factors 1152 

Valve Service 11&3 

Centrifugal Fans 

Definitions, Formuln and Types of 

Fans 11»3 

Type of Fan Impellers 1170 

Parallel Operation 117A 

Beating and Ventilating 

Ash Handling Machinery, 
mscellaneous 

Heating 1177 

Newport News S. B. & D. D. Co.. 

Practice 1178 

U. S. Naval Specifications 1180 

Ventilation 1 181 

Ventilators 1184 

Combined Heating and Ventilation. 1189 

Thermofan System 1189 

SiroccoBone System 1191 

Ash Handling Machinery 1 192 

Whistle and Siren 119« 

Air Compresiort 

Proi)ertie» of Air 1 198 

Flow of Air : • . 1199 

Work of Compression 1200 

Air Compressors 1201 

Tenting Air Compressors 1203 

Operation and Maintenance 1204 

Deck Auziliariei 

Steering Gear 1206 

Automatic Follow up Gear for 

Steering Engine 1218 

Rudder Torotie 1218 

Sise of Steering Gear 1219 

Steering Gear Control 1222 

Windlasses 1230 

Cargo Winches 1234 

Electric Winches 1241 

Warping Winches 1242 

Capstans 12*2 



CONTENTS 



XV 



SECTION 11 

PIPINa, ▼ALVXS AND FITTINaS 
RKBUCINO ' VALYB8 AND PUMP OOVSBNOB8 

8TKAM TRAPS 

pm oovx&iNo AifD LAoonro 



FlplBfft YalTM and VlttinirB 

Pagb 

PUm 1245 

Mftteriab 1254 

Thickoeas 1261 

Strength 1262 

Pipe Benda and Ezpanaion 1266 

Pipe Connections: 

Pipe Threads 1271 

FUnoeB 1272 

FittinflB > 1284 

Pftinting Pipes 1290 

Zinc Boxes 1291 

Vslves 1291 

Globe. Angle and Cross 1294 

Cheek 1297 

Gate 1299 

Cocks and Blow-off 1801 

Tables 1302 

Safety and Relief Valves 1324 

Eadiieiiic VaItm and Fump Qorttmon 

Redneing Valves 1332 

Pump Governors 1339 



StMtm Trap* 

Pags 

Purpose 1340 

Types 1342 

Design 1343 

Ratings and Capacities 1346 

Installation, Care and Operation. . . 1346 

Testing 1347 

Specifications 1347 

Pipe OoTerlng and Lagging 

Heat Losses from Bare Metal 
Surfaces 1348 

Losses Through and Savings from 
Insulation 1350 

Standard Commercial Sixes, Pipe 
Covering 1368 

Pipe Covering Specifications 1359 



SECTION 12 



MA&DiS SLKCTSICAL INSTALLATION 



Paqb 

Methods of Installation: 

Classification Society Rules 1368 

Drawings 1364 

Wire Sises 1364 

Protection of Conductors 1365 

Types of Conductors 1360 

Generating Sets 1367 

Marine Switchboards 1371 

Ugditing System: 

Promts , 1371 

FHtingv 1372 



Paqs 

Running Lights '. . . 1373 

Lamps 1374 

Searchlights 1375 

Power System 1376 

Signalling Systems: 

Engine Telegraphs 1377 

Telephones 1377 

Fire Alarms 1377 

Submarine Signals 1378 

Radio Telegraph 1378 



SECTION 13 
LIFBRICATION AND LUB&ICANT8 



Paoe 

LabrieatMm 1381 

Friction 1381 

Lubricants: 

Mineral Oils 1S83 

Animal, Pish and VegeUble Oils. 1383 



Paob 

Fixed Oils and Compound Oils. . . 1383 

Greases 1384 

Graphite 1385 

Selecting Lubricant for Service 1386 

Engine and Machine Oil 1386 

Forced Lubrication Oils 1388 



XVI 



COS TK NTS 



Pacub 

Marine Engine Oik 1388 

Cylinder Ofls 1391 

Air Compreeaor Oil 1392 

loe Machine Oil 1392 

Motor Oibi 1392 

Physical Constants of Oils: 

Viscosity 1394 

Flash and Fire 1394 



Pa OB 

Emukifieation Test 1395 

Water and Sediment 1395 

Cold Test 1396 

Specifie GraTity 1397 

Color 1397 

Odor 1398 

Carbon 1399 



SECTION 14 



MXASUBINQ HORSEPOWER OF BCARXNE BHOIKES 



Paor 

Power 1403 

Indicators and Indicator Cards 1404 

Elssential Requirements of Good 

Indicator 1405 

Indicator Springs 1406 

Indicator Cord 1406 

Reducing Motions 1406 

Taking the Card 1408 

Indicator Cards 1409 

Combined Indicator Cards 1410 

Effect of Varying Cut-off on 

Power Distribution 1411 



Pagx 

Steam Consumption from Indi- 
cator Card 1412 

Calculating the I. H. P.: 

M. E. P •: 1412 

Planimeters 1413 

Manograph 1416 

Torsion Meters: 

Shaft Calibration 1417 

Gar>'-Cumming8 Torsion Meter. . 1420 
Hopkinson Thring Torsion Meter 1423 
Denny-Edgecombe Torsion Meter 1425 



SECTION 16 



TESTS, TRIALS AND INSPECTION OF MACHINERT, 
CLASSinCATION SOCIETIES 



Tests, Trlalji, Inspections 



Pacs 



Tests for Machinery before same is 

placed oif board 1429 

Pioing before same is placed on 

board 1430 

Machinery after same is placed on 

board 1431 

Machinery, preparatory to Trials 1433 

Trials of Machinery 1434 

Dock Trials 1435 

Contract Acceptance Trials 1436 

Commissioning, Poet Repair and 
laying Up Trials 1448 

CUssifloAtion Socistiss 

Names and Addresses of Societies. . 1450 

Steamboat Inspection Service 1450 

Publications 1451 

Legal Status 1451 

Bureau of Standards 1452 

Publications 1452 

Legal Status 1452 

American Bureau of Shipping 1452 

Publications 1453 

Legal Status 1453 



Paq* 

Amerlesn Sodety of Testing Materi- 
als 1463 

PurmMe 1454 

Publioations 1454 

American Society of Mechanical 

Engineers 1454 

Publications 1454 

Legal Status 1454 

Bureau of Explosives ^. . . 1455 

American Institute of ElectricAl 

Engineers 1455 

Publioations 1456 

Leeai SUtus 1456 

Master Car Builder's Association. . . 1456 

Purpows 1456 

Ameri(fi&n Railway ' Engineering 

Association 1457 

Purpose 1457 

Publications 1457 

Legal Status 1467 

America Institute <lf Weights and 

Measures 

Porpooe 

Publications 

American Society of Naval Engl* 

neen 

Purpose 

Pttbiication 



1457 
1457 
1458 

1458 
1458 
1458 



SECTION 1 

MATHEMATICAL TABLES AND FORMULJB 

AND 
MECHANICS OF RIGID BODIES 

BY 

MA7SON W. TORBBT, Capiain of EnRra., U.8.C.G., B. Mar. E., 
Mem. Council, A.S.N.E. 



CONTENTS 



KATHSMATICAL TABLB8 AND 
WOBMUhM 

Paqb 

Common LocikrithinB 2 

Trigonometric Funetions 

Decimal Equivalents 11 

Cireles (Cireuinferencefl and Arean) . .* 12 

Ocnveraion Tables: 

Acceleration of Gravity 14 

Forces 14 

Ltngtha 15 



Areas 

Volumes and Capacities. 
Velocities 



Pressures 

Energy, Wofkp Heat 



15 
IG 
IG 
17 
17 
18 



Paqb 

Power 18 

Density. 19 

Heat Transmifision and Conduction 19 

Trigonometric Formulee 20 

Di£Ferential Formule 22 

Indefinite Integral!) 23 

Definite Integrslfl 25 

MSCHANIC8 or RIGID BODIES 

By M. W. TORBET 

Definitions 27 

Units •. 27 

Kinematics 29 

Statics 32 

Kinetics 38 



MATH IS MAT! UAli TA tSJjtSS 



COMMON I.OOABXTHM8 (tpecioZ tabU) 



p 





1 


1 


S 


4 


• 


• 


t 


8 





9^ 


1.00 


0.0000 


0004 


0009 


0013 


0017 


0022 


0026 


0030 


0035 


0039 


4 


IjOI 


0043 


0048 


0052 


0056 


0060 


0065 


0069 


0073 


0077 


0082 




\m 


0086 


0090 


0095 


0099 


0103 


0107 


0111 


0116 


0120 


0124 




1.03 


0128 


0133 


0137 


0141 


0145 


0149 


0154 


0158 


0162 


0166 




1.04 


0170 


0175 


0179 


0183 


0187 


0191 


0195 


0199 


0204 


0208 




1J05 


0212 


QZI6 


0220 


0224 


OZ28 


0233 


0237 


0241 


0245 


0249 




\0b 


0253 


0257 


0261 


0265 


0269 


0273 


0276 


0282 


0286 


0290 




1.07 


0294 


0296 


0302 


0306 


0310 


0314 


0316 


0322 


0326 


0330 




1.06 


0334 


0338 


0342 


0346 


0350 


0354 


0358 


0362 


0366 


0370 


« 


\m 


0374 


0378 


0382 


0366 


0390 


0394 


0396 


0402 


0406 


0410 




i.io 


0.0414 


0418 


0422 


0426 


0430 


0434 


0438 


0441 


0445 


0449 




1.11 


0453 


0457 


0461 


0465 


0469 


0473 


0477 


0481 


0484 


0488 




1.12 


0492 


0496 


0500 


0504 


0506 


0512 


0515 


0519 


0523 


0527 




1.13 


0531 


0535 


0538 


0542 


0546 


0550 


0554 


0558 


0561 


0565 




1.14 


0569 


0573 


0577 


0580 


0584 


0586 


0592 


0596 


0599 


0603 




1.15 


0607 


0611 


0615 


0618 


0622 


0626 


0630 


0633 


0637 


0641 


• 


1.16 


0645 


0646 


0652 


0656 


0660 


0663 


0667 


0671 


0674 


0678 




1.17 


0662 


0686 


0689 


0693 


0697 


0700 


0704 


0706 


0711 


0715 




1.18 


0719 


0722 


0726 


0730 


0734 


0737 


0741 


0745 


0748 


0752 




1.19 


0755 


0759 


0763 


0766 


0770 


0774 


0777 


0781 


0785 


0786 




i.to 


0.0792 


0795 


0799 


0803 


0806 


0810 


0813 


0817 


0621 


0624 




\2\ 


0628 


0631 


0635 


0639 


0642 


0646 


0649 


0853 


0856 


0660 




1.22 


0664 


0667 


0671 


0874 


0678 


0881 


0685 


0688 


0892 


06% 




Mi 


0899 


0903 


0906 


0910 


0913 


0917 


0920 


0924 


0927 


0931 




\2A 


0934 


0938 


0941 


0945 


0946 


0952 


0955 


0959 


0962 


0966 




1.25 


0969 


0973 


0976 


0960 


0963 


0986 


0990 


0993 


0997 


1000 


3 


1.26 


1004 


1007 


1011 


1014 


1017 


1021 


1024 


1028 


1031 


1035 




1J7 


1038 


1041 


1045 


1048 


1052 


1055 


1059 


1062 


1065 


1069 




1J8 


1072 


\m 


1079 


1062 


1066 


1069 


1092 


1096 


1099 


1103 




1.29 


1106 


1109 


1113 


1116 


1119 


1123 


1126 


1129 


1133 


1136 




i.to 


0.1139 


1143 


1146 


1149 


1153 


1156 


1159 


1163 


1166 


1169 




1.31 


1173 


1176 


1179 


1183 


1186 


1189 


1193 


1196 


1199 


1202 




132 


1206 


1209 


1212 


1216 


1219 


1222 


1225 


1229 


1232 


1235 




1.33 


1239 


1242 


1245 


1248 


1252 


1255 


1258 


1261 


1265 


1268 




134 


1271 


1274 


1278 


1281 


1284 


1287 


1290 


1294 


1297 


1300 




135 


1303 


1307 


1310 


1313 


1316 


1319 


1323 


1326 


1329 


1332 




136 


1335 


1339 


1342 


1345 


1348 


1351 


1355 


1358 


1361 


1364 




137 


1367 


1370 


1374 


1377 


1380 


1383 


' 1386 


1389 


1392 


1396 




136 


1399 


1402 


1405 


1406 


1411 


1414 


1418 


1421 


1424 


1427 




139 


1430 


1433 


1436 


1440 


1443 


1446 


1449 


1452 


1455 


1458 




1.40 


0.1461 


1464 


1467 


1471 


1474 


1477 


1480 


1483 


1486 


1489 




,1.41 


1492 


1495 


1496 


1501 


150^ 


1508 


1511 


1514 


1517 


1520 




1.42 


1523 


1526 


1529 


1532 


1535 


1538 


1541 


1544 


1547 


1550 




1.43 


1553 


1556 


1559 


1562 


1565 


1569 


1572 


1575 


1578 


1561 




1.44 


1564 


1587 


1590 


1593 


1596 


1599 


1602 


1605 


1606 


1611 




1.45 


1614 


1617 


1620 


1623 


1626 


1629 


1632 


1635 


1638 


1641 




1.46 


1644 


1647 


1649 


1652 


1655 


1658 


1661 


1664 


1667 


1670 




1.47 


1673 


1676 


1679 


1682 


1685 


1688 


1691 


1694 


1697 


1700 




1.46 


1703 


1706 


1706 


1711 


1714 


1717 


1720 


1723 


1726 


1729 




1.49 


1732 


1735 


1738 


1741 


1744 


1746 


1749 


1752 


1755 


1758 





Moving the d«otma] fxnnt n places to the right [or left] in the number requires addins +  
(or — n] in the body ox the table (see p. 4). 



J 



MATHEMATICAL TABLES 



OOMMOK LOOABITHMS {apeeial table, eanHnued) 



IJ5 
176 
IJT 
I.7S 
IJ9 

i.M 
\M 

\M 
IM 
IM 

1.85 
1.86 
W 
}M 
\J» 

1.90 

1.91 
1.92 

\,n 

1.94 

1.95 
1.96 
1.97 
1.98 
1.99 



Jl 


O 


1 


1 


8 


4 


8 


8 


T 








IJO 


ai76i 


1764 


1767 


1770 


1772 


1775 


1778 


1781 


1784 


1787 


131 


1790 


1793 


1796 


1796 


1801 


1804 


1807 


1810 


1813 


1816 


152 


1018 


1821 


1824 


1827 


1830 


1833 


1836 


1838 


1841 


18M 


133 


1047 


1850 


1853 


18S5 


1858 


1861 


1864 


1867 


1870 


1872 


134 


1875 


1878 


1881 


1884 


1886 


1889 


1892 


1895 


1098 


1901 


135 


1905 


1906 


1909 


1912 


1915 


1917 


1920 


19Z3 


1926 


1928 


136 


1951 


1934 


1997 


1940 


1942 


1945 


1948 


1951 


1953 


1956 


137 


1959 


1962 


1965 


1967 


1970 


1973 


1976 


1978 


1961 


1984 


138 


1967 


1909 


1992 


1995 


1996 


iooo 


2003 


2006 


2009 


2011 


139 


2014 


2017 


2019 


2022 


2025 


2028 


2090 


2033 


2036 


2038 


1.80 


0J04I 


2044 


2047 


2049 


2052 


2055 


2057 


2060 


2063 


2066 


Ul 


2068 


2071 


2074 


2076 


2079 


2062 


2084 


2087 


2090 


2092 


t.62 


2095 


20W 


2101 


2103 


2106 


2109 


2111 


2114 


2117 


2119 


1.65 


2122 


2125 


2127 


2130 


2133 


2135 


2138 


2140 


2143 


2146 


\M 


2146 


2151 


2154 


2156 


2159 


2162 


2164 


2167 


2170 


2172 


\J6& 


2175 


2177 


2180 


2183 


2185 


2188 


2191 


2193 


2196 


2198 


Ij66 


2201 


2204 


2206 


2209 


2212 


2214 


2217 


2219 


2222 


2225 


Ii7 


2227 


2230 


2232 


2235 


2238 


2240 


2243 


2245 


2248 


2251 


lis 


2253 


2256 


2258 


2261 


2263 


2266 


2269 


2271 


2274 


2276 


1i9 


2279 


2281 


2284 


2287 


2289 


2292 


2294 


2297 


2299 


2302 


LTO 


OJ304 


2307 


2310 


2312 


Z3I5 


2317 


2320 


2322 


2325 


2327 


1JI 


2330 


2333 


2335 


2338 


2340 


2343 


2345 


2348 


2350 


2353 


1J2 


2355 


2358 


2360 


2363 


2365 


2368 


2370 


2373 


2375 


2378 


IJ3 


2380 


2383 


2385 


2388 


2390 


2393 


2»5 


2398 


2400 


2403 


IJ4 


2405 


2408 


24t0 


2413 


2415 


2418 


2420 


2423 


2425 


2428 



2430 
2455^ 



2504 
2529 

0.2553 
2577 
2601 
2625 
2648 

2672 
2695 
2718 
2742 
2765 

0J788 
2810 
2833 
2856 
2878 

2900 

2923 
2945 
2967 
2989 



2433 
2458 
2482 
2507 
2531 

2555 

2579 
2603 
2627 
2651 

2674 
2607 
2721 
2744 
2767 

2790 
2813 
2835 
2858 



2903 
2925 
2947 
2969 
2991 



2435 
2460 
2485 
2509 
2533 

2558 
2582 
2605 
2629 
2653 

2676 
2700 
2723 
2746 
2769 

2792 
2815 
2838 

2860 
2882 

2905 
2927 
2949 
2971 
2993 



2438 
2463 
2487 
2512 
2536 

2560 
2584 
2608 
2632 
2655 

2679 
2702 
2725 
2749 
2772 

2794 
2817 
2840 
2862 
2885 

2907 
2929 
2951 
2973 
2995 



2440 
2465 
2490 
2514 
2538 

2562 
2586 
2610 
2634 
2658 

2681 
2704 
2728 
2751 
2774 

2797 
2819 
2842 
2865 
2887 

2909 

2931 

2953 

2975 

2997 



2443 
2467 
2492 
2516 
2541 

2565 
2589 
2613 
2636 
2660 

2683 
2707 
2730 
2753 
2776 

2799 
2822 
2844 
2867 
2889 

2911 
2934 
2956 
2978 
2999 



2445 
2470 
2494 
2519 
2543 

2567 
2591 
2615 
2639 
2662 

2686 
2709 
2732 
2755 
2778 

2801 
2824 
2847 
2869 
2891 

2914 
2936 
2958 

2980 
3002 



2448 
2472 
2497 
2521 
2545 

2570 
2594 
2617 
2641 
2665 



2711 
2735 
2758 
2781 

2804 
2^ 
2849 
2871 
2894 

2916 
2938 

2960 
2982 
3004 



2450 
2475 
2499 
2524 
2548 

2572 
2596 
2620 
2643 

26V, 

2690 
2714 
2737 
2760 
2783 

2806 
2828 
2851 
2874 
2896 

2918 
2940 
2962 
2984 
3006 



2453 
2477 
2502 
2526 
2550 

2574 
2598 
2622 
2646 
jDvy 

2693 
2716 
2739 
2762 
2785 



2831 
2853 
2876 
2898 

2920 
2942 
2964 
2986 
3008 



MATHEMATICAL TABLES 



COMMON LOGARITHMS 



1 





1 


S 


t 


6 





f 


T 


8 





!^- 


g-^ 






















<-3 


1.0 


0.0000 


00«3 


0006 


0128 


OI70 


0212 


0253 


0294 


0334 


0374 




1.1 


0414 


0453 


0492 


0531 


0569 


0607 


0645 


0682 


0719 


0755 




1.2 


0792 


0628 


0864 


0899 


0934 


0969 


1004 


1038 


1072 


1106 




13 


1139 


1173 


1206 


1239 


1271 


1303 


1335 


1367 


1399 


1430 


t 


K4 


1461 


1492 


1523 


1553 


1584 


1614 


1644 


1673 


1703 


1732 


13 


1761 


1790 


1818 


1847 


1875 


1903 


1931 


I9S9 


1967 


2014 


% 


1.6 


2041 


2068 


2095 


2122 


2148 


2175 


2201 


2227 


2253 


2279 


J 


17 


2304 


2330 


2355 


2380 


2405 


2430 


2455 


2480 


2504 


2529 


JK% 


IjB 


2553 


2577 


2601 


2625 


2648 


2672 


2695 


2718 


2742 


2765 


1 


1.9 


2788 


2810 


2833 


2856 


2878 


2900 


2923 


2945 


2967 


2989 


S.0 


03010 


3032 


3054 


3075 


3096 


3118 


3139 


3160 


3181 


3201 


21 


2.1 


3222 


3243 


3263 


3284 


3304 


3324 


3345 


3365 


3385 


3404 


20 


12 


3424 


3444 


3464 


3483 


3502 


3522 


3541 


11^ 


3579 


3596 




13 


3617 


3636 


3655 


3674 


3692 


3711 


3729 


3766 


3784 




2.4 


3802 


3820 


3838 


3656 


3874 


3892 


39(» 


3927 


3945 


3962 




23 


3979 


3997 


4014 


4031 


4048 


4065 


4062 


4099 


4116 


4133 




2j6 


4150 


4166 


4183 


4200 


4216 


4S2* 


4249 


4265 


4281 


4298 




27 


4314 


4330 


Am 


4362 


437S 


4393 


4409 


4425 


4440 


4456 




2JB 


4472 


4467 


4502 


4518 


4533 


4548 


4564 


4579 


4594 


^ 




2.9 


4624 


4699 


4654 


ASJJH 


4683 


MJOA 
nvVO 


4713 


4726 


4742 




8.0 


0.4771 


4786 


4800 


4814 . 


4829 


4843 


4857 


4871 


4886 


4900 




3.1 


4914 


4928 


4942 


4955 


4%9 


4983 


4997 


5011 


5024 


3038 




3.2 


5051 -. 


5065 


5079 


5092 


5105 


5119 


5132 


5145 


5159 


5172 




33 


5185 


5196 


5211 


5224 


5237 


5250 


5263 


5276 


5289 


5302 




3^ 


5315 


5328 


5340 


5353 


5366 


5378 


5391 


5403 


5416 


5428 




33 


5441 


5453 


5465 


5478 


5490 


5502 


5514 


5527 


5539 


5551 




3j6 


5563 


5575 


5587 


5599 


5611 


5623 


5635 


5647 


5658 


5670 




37 


5682 


5694 


5705 


5717 


5729 


5740 


5752 


5763 


5775 


5786 




3^ 


5798. 


5809 


5821 


5832 


5843 


5855 


5866 


5877 


5888 


5899 


11 


3.9 


5911 


5922 


5933 


5944 


5955 


5966 


5977 


5988 


5999 


6010 


11 


4.^ 


0.6021 


6031 


6042 


6053 


6064 


6075 


6065 


6096 


6107 


6117 


11 


4.1 


6128 


6138 


6149 


6160 


6170 


6180 


6191 


6201 


6212 


6222 


10 


4.2 


6232 


6243 


6253 


6263 


6274 


6284 


6294 


6304 


6314 


6325 


K) 


43 


6335 


6345 


6355 


6365 


6375 


6385 


6395 


6405 


6415 


6425 


10 


4.4 


6435^ 


6444 


6454 


6464 


6474 




6493 


6503 


6513 


6522 


10 


43 


6532 


6542 


6551 


6561 


6571 


6580 


6590 


6599 


6609 


6618 


10 


4j6 


6628 


6637 


6646 


6656 


6665 


6675 


6684 


6693 


6702 


6712 


10 


47 


6721 


6730 


6739 


6749 


6758 


6767 


6776 


6785 


6794 


6803 


9 


4^ 


6812 


6821 


6810 


6839 


6848 


6857 


6866 
6^ 


6875 


6884 


6893 


9 


4.9 


6902 


6911 


6920 


6928 


6937 




6964 


6972 


6981 


9 



log r - 0.4971 
log e - 0.4343 



log t/2 = 0.1001 log T* 
log (0.4343) =. 0.6378 - 1 



0.0013 



log V", - 0.2486 



These two pages give the oommon logarithms of numbers between 1 and 10, correct 
to four places. Moving the decimal point n pTacee to the right (or left] in the humber ia 
equivalent to adding n [or -^n] to the logarithm. Thus, log 0.017453 i» 0.2410 ~ 2, 
which may also be written 2.2410 or 8.2410 - 10. 

log (ab) - log a + log b log (a^) • ^ log o 



log (-J-J — log a — log h 



Iog( vo) - w^log 



COSTSNTS 



XV 



SECTION 11 

PIPIHQp VALVX8 AND nTTINGW 
RXDUCINO VALVES AND PUMP QOVIBNOBS 

8TXAM T&AP8 
PIPX GOVE&INO AND LAaOING 



PIplBC, ValTM uid ItttliiCB 

Page 

PhiM 1245 

Materials 1254 

ThickiMM 1261 

Stiourth 1262 

Pipe Bends and Expansion 1260 

Pipe ConneetionB: 

Kpe Threads 1271 

FliAsee 1272 

FSttinp > 1284 

Fainting Pipes 1290 

Zuc Boxes 1291 

Vtlrm 1291 

Globe. Ansle and Cross 1294 

Check 1291 

Gate 1299 

Cocks and Blow-off 1301 

Tables 1302 

Safety and Relief Valves 1324 

BftiTurfnc VaIym and Pump CtoYeimon 

Reducing Valves 1332 

Pump Governors 1339 



Steam Trap* 

Paob 

Purpose 1340 

Types 1342 

Design 1343 

Ratings and Capacities 1345 

Installation, Care and Operation. . . 1346 

Testing 1347 

Specifications 1347 

Pip« Coverlnir and Lagging 

Heat Losses from Bare Metal 
Surfaces 1348 

Losses Through and Savings from 
Insulation 1350 

Standard Commercial Sixes, Pipe 
Covering 1358 

Pipe Covering Specifications 1359 



SECTION 12 
liABIMX SLXGT&ICAL INSTALLATION 



Page 

Methods of Inat^tion: 

Classifieation Society Rules 1363 

Drawings 1364 

WireSisea 1364 

Protection of Conductors 1865 

Types of Conductors 1366 

Generating Sets 1367 

Marine Switchboards 1371 

Sremts 1371 

Fittings rr 1372 



Paob 

Running Lights '. . . 1373 

Lamps 1 374 

Searchlights 1375 

Power System 1376 

SignfJling Systems: 

Engine Telegraphs 1377 

Telephones 1377 

Fire Alarms 1377 

Submarine Signals 1378 

Radio Telegraph 1378 



SECTION 13 
LUBRICATION AND LUBBIOANTS 



Paob 

LobrioatMB 1381 

Frietion 1381 

Idbricants: ^^„ 

Oils 1883 

Fish and Vegetable Oils. 1383 



Paqx 

Fixed Oils and Compound Oils. . . 1383 

Greases 1384 

Graphite 1385 

Selecting Lubricant for Service 1386 

Engine and Machine Oil 1386 

Forced Lubrication Oils 1388 



6 



MATHEMATICAL TABLES 



TRiaONOMSTBIG rUNCTIONS (at intervals of 100 

Annex — 10 In oolumns marked*. 



De- 
grees 


Rar 
dians 


Sines 


Cosines 


Tangents 


Cotangents 


\ 








Nat. 


Log.* 


Nat. Log.* 


Nat. 


Log.* 


Nat. Log. 






o-oy 


0.0000 


joooo 


00 


1.0000 0/X)00 


jOOOO 


«9 


0» OS 


13708 


90* OIK 


10 


00029 


.0029 


7.4637 


1.0000 .0000 


J00J9 


7.4637 


34377 23363 


13679 


50 


20 


00058 


j»m 


J648 


1.0000 .0000 


.0058 


7648 


171.89 7352 


13650 


40 


30 


00067 


.WS7 


.9408 


1.0000 .0000 
a9999 JOOOO 


.0087 


.9409 


11439 X)591 


13621 


30 


40 


0.0116 


.0116 


%M5S 


^116 


84)658 


85.940 1.9342 


13592 


10 


50 


Oi)145 


i)l45 


.1627 


.9999 jOOOO 


X)145 


.1627 


68.750 J8373 


13563 


10 


I^^OO* 


0.0175 


JH75 


8JB419 


OQOS OOQAO 


J0175 


87419 


57790 17581 


13533 


m^wy 


10 


0.0204 


.0204 


J068 


ooott OQoa 


.0204 


J069 


49.104 .6911 


13504 


50 


20 


0.0233 


jam 


.3A68 


onnry fHMm 
»rrft mfryy 


.0233 


.J0o7 


42.964 .6331 


13475 


40 


30 


0.0262 


.0262 


.4179 


0QQ7 OQQO 


.0262 


.4181 


38.188 3819 


13446 


30 


40 


0.0291 


.0291 


.4637 


.9996 .9998 


.0291 


.4638 


34368 3362 


13417 


20 


50 


0.0320 


jom 


.5050 


.9995 .9998 


in20 


JQ53 


31742 .4947 


13388 


10 


2*00* 


0.0349 


i)349 


83428 


.9994 9.9997 


J)349 


83431 


28.636 1.4569 


13359 


880 00^ 


10 


0.0378 


.0378 


.5776 


.9993 .9997 


J0378 


3779 


26.432 .4221 


13330 


50 


20 


0.0407 


JMN 


.6097 


nmvy odok. 


.0407 


.6101 


24.542 3899 


13301 


40 


30 


0.0436 


i)436 


.6397 


.9990 .9996 


.0437 


.6401 


22.904 3599 


13272 


30 


40 


0.0465 


.0465 


.6677 


,9989 .Vrfi 


i>466 


.6682 


21.470 3318 


13243 


20 


50 


0.0495 


i>494 


.6940 


•9988 *yrrj 


i)495 


.6945 


20706 3055 


13213 


10 


rw 


0.0524 


.0523 


87188 




J0S24 


87194 


19.081 17806 


13184 


OT^OO' 


10 


0.0553 


.0552 


.7423 


.9985 .9993 


.0553 


.7429 


18.075 7571 


13155 


50 


20 


0.0582 


.0581 


.7645 


.9983 .9993 


.0582 


.7652 


17.169 7348 


13126 


40 


30 


0.0611 


.0610 


7857 


.9981 .9992 


.0612 


.7865 


16.350 7135 


1.5097 


30 


40 


0.0640 


.0640 


.8059 


.9980 .9991 


.0641 


.8067 


15.605 .1933 


13068 


20 


50 


0.0669 


i)669 


.8251 


.9978 .9990 


jom 


U126I 


14.924 .1739 


13039 


10 


4<»00' 


0.0698 


MM 


8.8436 


.9976 9.9969 


.0699 


8.8446 


14301 1.1554 


13010 


86<»0O' 


10 


0.0727 


JNU 


.8613 


.9974 .9989 


.0729 


.8624 


13727 .1376 


1.4961 


SO 


20 


0.0756 


.0756 


.8783 


.9971 .9988 


.0758 


.8795 


13.197 .1205 


1.4952 


40 


30 


0.0785 


.0785 


J»46 


.9969 .9987 


iy787 


.8960 


12.706 .1040 


I.49Z3 


30 


40 


0.0814 


.0814 


.9104 


.9967 .9986 


.0816 


.9118 


12.251 .0682 


1.4893 


20 


50 


0.0644 


.0843 


.9256 


.9964 .9985 


.0846 


.9272 


11006 J0728 


1.4864 


10 


5*00' 


0.0873 


.0872 


8.9403 


.9962 9.9983 


JOSfS 


8.9420 


11.430 1.0580 


1.4835 


85*00' 


10 


0.0902 


.0901 


.9545 


.9959 .9982 


.0904 


.9563 


11.059 .0437 


1.4806 


50 


20 


0.0931 


.0929 


.9682 


.9957 .9981 


i)934 


.9701 


10712 J0299 


1.4777 


/ 40 


30 


0.0960 


.0958 


.9816 


.9954 .9980 


.0963 


.9836 


10385 JO\M 


1.4748 


30 


40 


0.0989 


.0987 


.9945 


.9951 .9979 


.0992 


.yyoo 


10.078 .0034 


1.4719 


20 


50 


0.1018 


.1016. 


9J0fO0 


.9948 .9977 


.1022 


9.0093 


97882 0.9907 


1.4690 


10 


e*" oo' 


0.1047 


.1045 


9X)192 


.9945 9.9976 


.1051 


9.0216 


93144 0.9784 


1.4661 


84'>00' 


10 


0.1076 


.1074 


.0311 


.9942 .9975 


.1080 


.0336 


97553 .9664 


1.4632 


50 


20 


0.1105 


.1103 


0426 


.9939 .9973 


.1110 


.0453 


9.0098 .9547 


1.4603 


40 


30 


0.1134 


.1132 


J0539 


.9936 .9972 


.1139 


.0567 


87769 .9433 


1.4574 


30 


40 


0.1164 


.1161 


.0648 


.9932 .9971 


.1169 


.0678 


83555 .9322 


1.4544 


20 


50 


0.1193 


.1190 


.0755 


.9929 .9969 


.1198 


JN96 


83450 .9214 


1.4515 


10 


T> tjfy 


0.1222 


.1219 


9.0659 


.9925 9.9968 


.1228 


9.0691 


8.1443 0.9109 


1.4486 


83*00' 


10 


0.1251 


.1248 


J096\ 


.9922 .9966 


.1257 


.0995 


7.9530 .9005 


1.4457 


50 


#20 


0.1280 


.1276 


.1060 


.9918 .9964 


.1287 


.1096 


7.7704 .8904 


1.4428 


40 


30 


0.1309 


.1305 


.1157 


.9914 .9963 


.1317 


.1194 


73958. .8806 


1.4399 


30 


40 


0.1338 


.1334 


.1252 


.9911 .9961 


.1346 


.1291 


7.4287 .8709 


1.4370 


20 


50 


0.1367 


.1363 


.1345 


.9907 .9959 


.1376 


.1385 


77687 .8615 


1.4341 


10 


ff W 


0.1396 


.1392 


9.1436 


.9903 9.9958 


.1405 


9.1478 


7.1154 0.8522 


1.4312 


82*00' 


10 


0.1425 


.1421 


.1525 


.9899 .9956 


.1435 


.1569 


6.9682 .8431 


1.4283 


SO 


20 


0.1454 


.1449 


.1612 


.9894 .9954 


.1465 


.1658 


6.8269 .8342 


1.4254 


40 


30 


0.1484 


.1478 


.1697 


.9890 .9952 


.1495 


.1745 


6.6912 .8255 


1.4224 


30 


40 


0.1513 


.1507 


.1781 


.9886 .9950 


.1524 


.1831 


6 5606 3169 


1.4195 


20 


50 


ai542 


.1536 


.1863 


.9881 .9948 


.1554 


.1915 


6.4348 .8065 


1.4166 


10 


^w 


0.1571 


.1564 


9.1943 


.9877 9.9946 


.1584 


9.1997 


63138 0.8003 


1.4137 


81* OO' 






Nat. 


Log.* 


Nat. Log.* 


Nat. 


Log.* 


Nat. Log. 










Cosines 


Sines 


Potangents 


Tangents 


Ra- 


De- 
grees 







MATHEMATICAL TABLES 




7 


TRIOONOMSTUC yUNGTIONS (carainued) 




Annei — 10 in coiumss marked *. 








diaos 


Btnm 


CoahftM 


' Tangents 












Nat. Loc* 


Nat. Log.* 


Nat. Log.* 


Nat. Log. 






rw 


0.1571 


.1564 9.1943 


.9677 9.9946 


.1584 9.1997 


63138 0.8003 


1.4137 


SPOO" 


10 


0.1600 


.1593 2022 


.9672 .9944 


.1614 2078 


6.1970 .7922 


1.4108 


SO 


20 


0lI629 


.1622 2100 


.9068 .9942 


.1644 2158 


6.0844 2842 


1.4079 


40 


30 


0.1658 


.1650 2176 


.9863 .9940 


.1673 2236 


5.9758 7764 


1.4050 


30 


40 


a 1687 


.1679 2251 


.9858 .9938 


.17(8 2313 


5.8708 7687 


1.4021 


20 


50 


0LI7I6 


.1708 2324 


.9853 .9936 


.1733 2389 


57694 7611 


13992 


10 


WOO" 


0.1745 


.1736 92397 


.9848 9.9934 


.1763 92463 


5.6713 07537 


13963 


OO'OO' 


10 


0.1774 


.1765 2468 


.9643 .9931 


.1793 2536 


53764 7464 


13934 


SO 


20 


0.1804 


.1794 2538 


.9638 .9929 


.1823 2609 


5.4845 7391 


1.3904 


40 


30 


QLI833 


.1822 .2606 


.9833 .9927 


.1653 2680 


53955 7320 


13875 


30 


40 


0.1862 


.1851 2674 


.9627 .9924 


.1863 2750 


5.3093 7250 


13846 


20 


SO 


ai891 


.1880 2740 


.9822 .9922 


.1914 2819 


52257 7181 


13817 


10 


IPOO' 


0.1920 


.1908 92806 


.9616 9.9919 


.1944 92887 


5.1446 07113 


13788 


79^00' 


10 


0.1949 


.1937 2870 


.9811 .9917 


.1974 2953 


5.0658 7047 


13759 


SO 


20 


0LI978 


.1965 2934 


.9605 .9914 


2004 3020 


4.9894 .6980 


13730 


40 


30 


OJ007 


.1994 2997 


.9799 .9912 


2035 3065 


4.9152 .6915 


13701 


30 


40 


0JQ36 


2022 J058 


.9793 .9909 


2065 3149 


4.8430 .6851 


1.3672 


20 


SO 


QL2065 


-2051 3119 


.9787 .9907 


2095 3212 


4.7729 .6788 


13643 


10 


I2»00' 


0J094 


2079 93179 


.9781 9.9904 


2126 93275 


4.7046 OiinS 


13614 


78*00' 


10 


0J123 


2108 .3238 


.9775 .9901 


2156 3336 


4.6382 .6664 


13584 


SO 


20 


0JIS3 


2136 3296 


Swifff SKfTf 


2186 3397 


4.5Z36 .6603 


13555 


40 


30 


0L2182 


2164 3353 


Sf7& .9896 


2217 3458 


43107 .6542 


13526 


30 


40 


0J2I1 


2193 3410 


.9757 .9893 


2247 3517 


4.4494 .6483 


13497 


20 


SO 


0J240 


2221 3466 


.9750 .9890 


2278 3576 


43897 .6424 


13468 


10 


iroo* 


0J269 


2250 93521 


.9744 9.9687 


2309 93634 


43315 0^166 


13439 


7T>W 


10 


0J298 


2278 3575 


.9737 .9684 


2339 3691 


42747 .6309 


13410 


SO 


20 


02327 


2306 3629 


.9730 .9681 


2370 3748 


42193 .6252 


13381 


40 


30 


0L2356 


2334 3682 


.9724 .9678 


2401 3804 


4.1653 .61% 


1.3352 


30 


40 


0.2385 


2363 3734 


.9717 .9675 


2432 .3859 


4.1126 .6141 


13323 


20 


50 


02414 


2391 3786 


.9710 .9672 


2462 3914 


4.0611 .6086 


13294 


10 


M»00' 


0J443 


2419 93837 


.9703 9.9669 


2493 93968 


4.0108 0.6032 


1.3265 


76*00' 


10 


02473 


2447 .3887 




2524 .4021 


3.9617 3979 


13235 


SO 


20 


02SQ2 


2476 3937 


.96^9 .9063 


2555 .4074 


3.9136 3926 


13206 


40 


30 


02531 


2SM 3966 


.9681 .9659 


2586 .4127 


3.8667 3873 


1.3177 


30 


40 


02560 


2532 .4035 


.9674 .9656 


2617 .4176 


3.8206 .5822 


13148 


20 


SO 


02589 


2560 .4063 


.9667 .9653 


2648 .4230 


37760 3770 


13119 


10 


15*00" 


02618* 


2508 9^130 


.9659 9.9649 


.2679 9.4281 


37321 a5719 


13090 


75»00' 


10 


02647 


2616 .4177 


.9652 .9M6 


2711 A33I 


3.6891 3669 


13061 


SO 


20 


02676 


2644 .4223 


.9644 .9843 


.2742 .4381 


3.6470 3619 


1.3032 


40 


30 


0.2705 


2672 .4269 


.9636 .9639 


2773 Am 


3.6059 3570 


13003 


30 


40 


02734 


2700 .4314 


.9628 .9836 


2805 .4479 


33656 3521 


1.2974 


20 


SO 


02763 


2728 .4359 


.9621 .9632 


2836 -4527 


33261 3473 


12945 


10 


HFW 


02793 


2756 9.4403 


.9613 9.9828 


2867 9.4575 


3.4874 03425 


12915 


74* 00" 


10 


02822 


2784 .4447 


.9605 .9825 


2899 w4622 


3.4495 3378 


12886 


SO 


ao 


02851 


2812 .4491 


.9596 .9821 


2931 .4669 


3.4124 3331 


12857 


40 


30 


02880 


2840 .4533 


.9588 .9817 


2962 A7\h 


3.3759 32M 


12828 


30 


40 


02909 


2868 .4576 


.9500 .9814 


2994 ^762 


3.3402 3238 


1.2799 


20 


SO 


02938 


2896 .4618 


.9Sn .9810 


3026 .4808 


33052 3192 


12770 


10 


D»or 


02967 


2924 9.4659 


.9963 9.9606 


3057 9.4853 


32709 03147 


12741 


73*00' 


10 


02996 


2952 ^700 


.9555 .9602 




32371 3102 


12712 


SO 


20 


OJ025 


2979 ^41 


.9546 .9796 


3121 .4943 


3.2041 3057 


1.2683 


40 


30 


0J054 


3087 >4781 


.9537 .9794 


3153 .4967 


3.1716 3013 


12654 


30 


40 


0J063 


3035 .4821 


.9528 .9790 


3185 3031 


3.1397 .4969 


12625 


20 


SO 


0L31I3 


3062 .4861 


.9520 .9706 


3217 3075 


3.1084 .4925 


12595 


10 


iroo" 


03142 


3090 9.4900 


.9511 9.9782 


3249 93118 


3.0777 a4882 


12566 


72*00' 






Nat. Log.* 


Nat. Log.* 


Nat. Log.* 


Nat. Log. 




1 






CoiiaM 


Sines 


Cotangents 


Tangents 


Ra- 
dians 


De- 
grees 



MATTIl^AfATICAL TABLES 



TRiaONOMETBIC FUNCTIONS (continued) 

Annex — 10 in columns marked*. 



De- 
grees 


Ra- 
dians 


Sines Coaines 


Tangents 


Cotangents 








Nftt. Log. * 


Nat. 


Log.* 


Nat. 


Log.* 


Nat. Log. 






W'W 


03142 


3090 9.4900 


.9511 


9.9782 


3249 


9.51 f 8 


3.0777 a4882 


17566 


72* 00' 


10 


a3J7l 


3118 .4939 


.9502 


.9778 


3281 


3161 


3iH75 .4839 


17537 


50 


20 


0.3200 


3145 .4977 


.9492 


.9774 


3314 


3203 


3.0178 .4797 


l.i.508 


40 


30 


0.3229 


3173 3015 


.9483 


.9770 


3346 


3245 


2.9887 .4755 


1.2479 


30 


40 


0J258 


3201 3052 


.9474 


.9765 


.3378 


3287 


2.9600 .4713 


17450 


20 


50 


03287 


3228 3090 


.9465 


.9761 


3411 


3329 


2.9319 .4671 


17421 


10 


I9»00' 


0.3316 


3256 93126 


.9455 


9.9757 


3443 


93370 


2.9042 0.4630 


1.2392 


7P0O' 


10 


0.3345 


3283 3163 


.9446 


.9752 


3476 


3411 


2.8770 .4589 


17363 


50 


20 


03374 


.3311 3199 


.9436 


.9748 


3508 


3451 


2J502 .4549 


1.2334 


40 


30 


03403 


3338 3235 


.9426 


.9743 


.3541 


3491 


2 8239 .4509 


17305 


30 


40 


03432 


3365 3270 


.9417 


.9739 


3574 


3531 


2.7980 .4469 


17275 


20 


50 


03462 


3393 3306 


.9407 


.9734 


3607 


3571 


27725 .4429 


12246 


10 


2»>W 


03491 


3420 93341 


.9397 


9.9730 


3640 


93611 


27475 a4309 


17217 


70^00' 


10 


03520 


3448 3375 


.9387 


.9725 


3673 


3650 


2.7228 .4350 


17188 


50 


20 


03549 


3475 3m 


.937/ 


.9721 


3706 


3689 


2.6985 .4311 


17159 


• 40 


30 


03578 


.3502 3443 


.9367 


.9716 


3739 


3727 


2.6746 .4273 


17130 


30 


40 


a3607 


3529 3477 


.9356 


.9711 


3772 


3766 


2.6511 .4234 


17101 


20 


50 


03636 


3557 3510 


.9346 


.9706 


3805 


3804 


2.6279 .4196 


17072 


10 


2P00' 


0.3665 


.3584 93543 


.9336 


9.9702 


3839 


93842 


2.6051 0.4153 


17043 


69*00' 


10 


0.3694 


3611 3576 


.9325 


.9697 


.3872 


.5879 


23826 .4121 


17014 


50 


20 


0.3723 


.3638 .5609 


.9315 


.9692 


3906 


3917 


23605 .4083 


1.1985 


40 


30 


0.3752 


3665 3641 


.9304 


.9687 


3939 


3954 


23386 .4046 


1.1956 


30 


40 


0.3782 


.369: : .5673 
371$ 3704 


.9293 


.9682 


.3973 


.5991 


2.5172 .4009 


1.1926 


20 


50 


0.3811 


.9283 


.9677 


.4006 


.6028 


14960 3972 


1.1897 


10 


22»00' 


0.3840 


3746 9.5736 


.9272 


9.9672 


.4040 


9.6064 


2.4751 03936 


M868 


68* (MK 


10 


0.3869 


3773 3767 


.9261 


.9667 


.4074 


.6100 


2.4545 3900 


1.1839 


SO 


20 


0.3898 


3800 3798 


.9250 


.9661 


.4108 


.6136 


2.4342 3864 


1.1810 


40 


30 


0.3927 


3827 3828 


.9239 


.9656 


.4142 


J6I72 


2.4142 .3878 


1.1781 


30 


40 


0.3956 


.3854 3859 


.9228 


.9651 


.4176 


.6208 


23945 3792 


1.1752 


20 


50 


03965 


3881 3889 


.9216 


.9646 


.4210 


j6243 


23750 3757 


1.1723 


10 


23«00' 


0.4014 


3907 9.5919 


.9205 


9.9640 


.4245 


9.6279 


2.3559 03721 


1.1694 


67*00' 


10 


0.4043 


3934 3948 


.9194 


.9635 


.4279 


J6314 


23369 .3686 


1.1665 


50 


20 


0.4072 


3961 3978 


.9182 


.9629 


.4314 


.6348 


2.3183 3652 


1.1636 


40 


30 


0.4102 


3987 .6007 


.9171 


.9624 


.4348 


.6383 


27998 3617 


1.1606 


30 


40 


0.4131 


.4014 .6036 


.9159 


.9618 


^383 


.6417 


2.2817 3583 


1.1577 


20 


50 


0.4160 


.4041 .6065 


.9147 


.%13 


MU 


.6452 


27^7 3548 


1.1548 


10 


24-00' 


0.4189 


.4067 9.6093 


.9135 


9.9607 


.4452 


9.6486 


2.2460 03514 


1.I5I9 


66*00^ 


10 


0.4218 


.4094 .6121 


.9124 


.9602 


.4487 


.6520 


22286 3480 


1.1490 


50 


20 


0.4247 


.4120 .6149 


.9112 


.9596 


.4522 


.6553 


2.2113 3447 


1.1461 


40 


30 


0.4276 


.4147 .6177 


.9100 


.9590 


.4557 


.6587 


2.1943 3413 


1.1432 


30 


40 


0.4305 


.4173 .6205 


.9088 


.9584 


.4592 


^20 


2.1775 3380 


1.1403 


20 


50 


0.4334 


.4200 .6232 


.9075 


.9579 


.4628 


.6654 


2.1609 3346 


1.1374 


10 


25«»00' 


0.4363 


.4226 9.6259 


.9063 


9.9573 


.4663 


9.6687 


2.1445 03313 


1.1345 


65* OO' 


10 


0.4392 


.4253 .6286 


.9051 


.9567 




^20 


2.1283 3280 


1.1316 


50 


20 


0.4422 


.4279 .6313 


.9038 


.9561 


.4734 


.6752 


2.1123 3248 


1.1286 


40 


30 


0.4451 


.4305 .6340 


.9026 


.9555 


.4770 


.6785 


2.0965 3215 


1.1257 


30 


40 


0.4480 


.4331 .6366 


.9013 


.9549 


>4806 


.6817 


2.0809 3183 


1.1228 


20 


50 


0.4509 


^358 .6392 


.9001 


.9543 


.4841 


.6850 


2.0655 3150 


1.1199 


10 


26* 00' 


0.4538 


.4384 9.6418 


.89oo 


9.9537 


.4877 


9.6882 


2.0503 0-3118 


1.1170 


64* OO' 


10 


0.4567 


.4410 .6444 


.8975 


.9510 


.4913 


.6914 


2.0353 .-086 


1.1141 


50 


20 


0.4596 


.4436 .6470 


.8962 


.9524 


.4950 


.Ot^O 


2.0204 .3054 


1.1112 


40 


30 


0.4625 


.4462 .6495 


OttMt\ 


.9518 


.4986 


.6977 


2j0057 .3023 


1.1063 


30 


40 


0.46M 


.4488 .6521 


jme 


.9512 


.5022 


.7009 


1.9912 7991 


1.1054 


20 


50 


0.4683 


.4514 .6546 


.8923 


.9505 


.5059 


.7040 


1.9768 7960 


1.1025 


10 


27*00' 


a4712 


.4540 9.6570 


^10 


9.9499 


3095 


9J072 


1.9626 07928 


tj0996 


6r Qir 






Nat. Log.* 


Nat. 


Log.* 


Nat. 


Log.* 


Nat. Log. 










CfMines 


Sines 


Cotangents 


Tangents 


Ra- 
dians 


De- 
grees 



MATHEMATICAL TABLES 



9 



TBIGONOMXTBIC rUNCTIOlfS {continued) 

Annex — 10 in columoB marked.* 



De- 



10 
20 
30 
40 
50 

B^OO' 
10 
20 
30 
40 
50 

31" IT 
10 
20 
30 
40 
50 

WW 
10 
20 
30 
40 
1 50 

I to 

20 
30 
40 
50 

sroo' 

10 
I 20 
30 
40 
50 

10 
20 
30 
40 
SO 

3f 00" 
10 
20 
30 
40 
50 

9W 
10 
2D 
30 
40 
50 

IT or 



Ra- 
dians 



a47l2 
0.4741 
0.4771 
0.4000 
0.4029 
a40S6 

a4087 
0.4916 
0.4945 
0.4974 
0JQ03 
03032 

0.5061 
0.S09I 
0JI20 
0.5149 
0.5178 
03207 

0L5236 
0.5265 
0.5294 
03323 
0.5352 
03381 

0L54II 
03440 
03469 
03498 
03527 
0LSS56 

0.5585 
03614 
0.5643 
036n 
0.5701 
03730 

0.5760 
0.5789 
0.5818 
05847 
0.5876 
0.5905 

0.9934 
03S63 
0L5992 
0.6021 
0.6050 
0.6000 

0l6I09 
0.6138 
Oj6f67 
0.6196 
0.6225 
0L6254 

0l6283 



Bines 



Cosines 



Nat. 

.4540 
.4566 
.4592 
.4617 
.4643 

.4695 
.4720 
.4746 
.4772 
.4797 
.4823 

.4848 
.4674 
.4899 
.4924 
.4950 
.4975 

3000 

.5025 
3050 
3075 
3100 
3125 

3150 
3175 
3200 
3225 
3250 
3275 

3299 
3324 
.5348 
3373 
3398 
3422 

.5446 
3471 
3495 
3519 
3544 
3568 

3592 
3616 
3640 
3664 
3688 
3712 

3736 
3760 
3783 
.5807 
3831 
3854 

3878 



Log.* 

9.6570 
»6595 
.6620 
.6644 
.6668 
.6692 

9.6716 
J6740 
.6763 
.6787 
.6810 
.6833 

9.6856 
.6878 
.6901 
^23 

JDtW 
JBWO 

9.6990 
J012 
JOB 
J055 
.7076 
J097 

9.7118 
7139 
J160 
7181 
7201 
7222 

9.7242 
7262 
.7282 
7302 
7322 
7342 

9.7361 
7380 
.7400 
.7419 
.7438 
.7457 

97476 
7494 
7513 
7531 
7550 
.7568 

97586 
7604 
7622 
.7640 
.7657 
7675 

97692 



Nafc. Log.* 



CooiiMfl 



Nat. 

.8910 
.8897 

.8870 
.8857 
.8843 

.8829 
J816 
.8802 
.8788 
.8774 
J760 

.8746 
.8732 
.8718 
.8704 
.8689 
.8675 

.8660 
.8646 
.8631 
.8616 
J601 
.8587 

xm 

.8557 
.8542 
.8526 
.8511 

.8480 
.8465 
.8450 
.8434 
.8418 
.8403 

.8387 
.8371 
.8355 
.8339 
.8323 
.8307 

.8290 
.8274 
.8258 
.8241 
.8225 
w8208 

.8192 
.8175 
.8158 
.8141 
J124 
.8107 

J»90 



Log.* 

9.9499 
.9492 
.9486 
.9479 
.9473 

•TWO 

9.9459 
.9453 

.9439 
.9432 
.9425 

9.9418 
.9411 
.9404 
.9397 
.9390 
.9383 

9.9575 
.9368 
.9361 
.9353 
.9346 
.9338 

9.9331 
.9323 
.9315 
.9308 
.9300 
.9292 

9.9284 
.9276 
.9268 
.9260 
.9252 
.9244 

9.9236 
.9228 
.9219 
.9211 
.9203 
.9194 

9.9186 
.9177 
.9169 
.9160 
.9151 
.9142 

9.9134 
.9125 
.9116 
.9107 
.9098 
.9089 

9.9080 



Nat. Log. 



Sines 



Tangents 



Nat Log.* 

3095 97072 

3132 7103 

3169 7134 

.5206 .7165 

3243 7196 

3260 7226 

3317 9.7257 

3354 7287 

.5392 7317 

3430 .7348 

.5467 .7378 

3505 7406 

3543 9.7438 

.5561 7467 

.5619 .7497 

.5658 7526 

.5696 7556 

3735 7585 

3774 9.7614 

.5812 .7644 

3851 7673 

3890 .7701 

.5930 .7730 

3969 7759 

.6009 9.7788 

.6048 7816 

.6088 7845 

.6128 7873 

.6168 7902 

.6208 7930 

.6249 97958 

.6289 .7986 

.6330 .8014 

.6371 .8042 

.6412 .8070 

.6453 0)097 

.6494 9.8125 

.6536 .8153 

.6577 .8180 

.6619 .8208 

.6661 .8235 

.6703 .8263 

.6745 9.8290 

.6787 .8317 

.6830 0)344 

.6873 .8371 

.6916 .8398 

.6959 .8425 

.7002 9J452 

7046 .8479 

7089 .8506 

7133 .8533 

7177 .8559 

.7221 .8586 

7265 9.8613 

Nat. Log.* 



Cotangents 



Cotangents 



Nat. 

1.9626 
1.9486 
1.9347 
1.9210 
1.9074 
1.8940 



Log. 

07928 
7897 
7866 
7835 
7804 
7774 



1.8807 07743 
1.8676 7713 
1.8546 7683 
1.8418 7652 
1.8291 7622 
1.8165 7592 

1.8040 a2562 
1.7917 7533 
1.7796 7503 
1.7675 7474 
1.7556 7444 
17437 7415 

1.7321 07386 
1.7205 7356 
17090 7327 
1.6977 7299 
1.6864 7270 
1j6753 7241 

1.6643 07212 
1.6534 7184 
1.6426 7155 
1.6319 7127 
1.6212 7096 
1.6107 7070 

1.6003 0.2042 
1.5900 7014 
1.5796 .1986 
1.5697 .1958 
1.5597 .1930 
1.5497 .1903 

1.5399 0.1875 
1.5301 .1847 
1.5204 .1820 
1.5106 .1792 
1.5013 .1765 
1.4919 .1737 



1.4826 
1.4733 
1.4641 
1.4550 
1.4460 
1.4370 

1.4281 
1.4193 
1.4106 
1.4019 
1.3934 
13848 



0.1710 
.1683 
.1656 
.1629 
.1602 
.1575 

0.1546 
.1521 
.1494 
.1467 
.1441 
.1414 



13764 ai387 
Nat. Log. 



Tangents 



.0996 
.0966 
.0937 
.0906 
.0879 
.0850 

.0621 
.0792 
.0763 
.0734 
.0705 
.0676 

.0647 
.0617 
.0588 
.0559 
.0530 
.0501 

.0472 
.0443 
.0414 
.0385 
.0356 
0)327 

.0297 
.0268 
.0239 
.0210 
.0181 
0)152 

.0123 
.0094 
.0065 
0)036 
.0007 
0.9977 

0.9948 
0.9919 
0.9890 
0.9861 
0.9832 
0.9803 

09774 
0.9745 
0.9716 
0.9687 
0.9657 
a9628 

0.9599 
0.9570 
0.9541 
0.9512 
0.9483 
0.9454 

0.9425 



Ra- 



63*>00' 
50 
40 
30 
20 
10 

6r 00' 
50 
40 
30 
20 
10 

6r00' 
50 
40 
30 
20 
10 

60° 00' 
50 
40 
30 
20 
10 

59*00' 
50 
40 
30 
20 
10 

58*00' 
SO 
40 
30 
20 
10 

57*00' 
50 
40 
30 
20 
10 



56« 



55« 



00' 

50 

40 

30 

20 

10 

OO' 

50 
40 
30 
20 
10 

00' 



De- 
grees 



ii 



10 



MATHEMATICAL TABLES 



TBiaONOMBTBIC FUNCTIONS {conHnwd) 

Annex — 10 in columns marked *• 



SreoB 


Ra- 


Sines 


Cosines 


Tangents 


Cotangents 




. 




Nat. 


Log.» 


Nat. 


Log.* 


Nat. 


Log.* 


Nat. Log. 


1 




^W 


0.6283 


.5878 


9J692 


.8090 


9.9080 


7265 


9.8613 


13764 0L1387 


0.942^ 


54' Oy 


10 


0.6312 


3901 


7710 


.8073 


.9070 


.7310 




1.3680 .1361 


a9396 


50 


20 


0.6341 


3925 


7727 


.8056 


.9061 


7355 




I3»7 .1334 


0.9367 


40 


30 


0.6370 


3948 


7744 


JQ39 


.9052 


7400 


0)692 


13514 .1308 


a9338 


30 


40 


0.6400 


3972 


7761 


.8021 


.9042 


7445 


J718 


13432 .1282 


0.9308 


20 


50 


0.6429 


3995 


7778 


.8004 


.9033 


7490 


0)745 


13351 .1255 


0.9279 


10 


yrw 


0.6456 


.6018 


9.7795 


7986 


9.9023 


7536 


90)771 


13270 ai229 


0.9250 


53' OO* 


10 


0.6487 


.6041 


7811 


7969 


.9014 


.7581 


xm 


13190 .1203 


0.9221 


50 


- 20 


0.6516 


.6065 


7828 


7951 


.9004 


7627 


.8824 


1.3111 .1176 


0.9192 


40 


30 


0.6545 


.6088 


7844 


7934 


.8995 


7673 


.8850 


1.3032 .1150 


0.9163 


30 


40 


0.6574 


.6111 


7861 


7916 


J985 


.7720 


.8876 


17954 .1124 


0.9134 


20 


50 


0.6603 


.6134 


7877 


7898 


.8975 


7766 


.8902 


17876 .1098 


a9105 


10 


3r QO' 


0.6632 


.6157 


97893 


7880 


9.8965 


.7813 


9.8928 


17799 ai072 


0.9076 


52*00' 


10 


0.6661 


.6180 


7910 


7862 


.8955 


7860 


.8954 


17723 .1046 


0.9047 


50 


20 


0.6690 


.6202 


7926 


.7844 


.8945 


7907 


.8980 


17647 .1020 


0.9018 


40 


30 


0.6720 


.6225 


7941 


.7826 


.8935 


7954 


.9006 


17572 .0994 


0.8966 


30 


40 


0.6749 


.6248 


.7957 


.7808 


J925 


iXN)2 


.9032 


17497 J0968 


0.8959 


20 


50 


0.6778 


.6271 


7973 


7790 


.8915 


.8050 


.9058 


17423 .0942 


0.8930 


10 


59»00' 


0.6807 


.6293 


9.7989 


.7771 


9.8905 


.8098 


9.9084 


17349 0.0916 


0.8901 


51*00' 


10 


0.6836 


.6316 


.8004 


.7753 


in95 


A\¥i 


.9110 


17276 0»90 


0.8872 


50 


20 


0.6865 


.6338 


8020 


7735 


.ooo4 


.8195 


.9135 


1.2203 0W65 


0.8843 


40 


30 


0.6894 


j636I 


.8035 


7716 


J874 


.8243 


.9161 


17131 01639 


0.8814 


30 


40 


0.6923 


.6383 


.8050 


7698 


.8864 


.8292 


.9187 


17059 01613 


0.8785 


20 


50 


0.6952 


.6406 


.8066 


7679 


.8653 


.8342 


.9212 


1.1968 01786 


0.6756 


10 


40«»00' 


0.6981 


.6428 


9.8081 


7660 


9.8843 


.8391 


9.9238 


1.1918 a0762 


0.8727 


50* 00' 


10 


0.7010 


.6450 


.8096 


7642 


.8832 


.8441 


.9264 


1.1847 .0736 


0J696 


50 


20 


0.7039 


.6472 


.8111 


.7623 


.8821 


.8491 


.928% 


1.1778 .0711 


0.8666 


40 


30 


0.7069 


.6494 


.8125 


7604 


.8610 


.8541 


.9315 


1.1708 0M85 


0.8639 


30 


40 


0.7098 


j6517 


.8140 


7585 


JMOO 


.8591 


.9341 


1.1640 .0659 


0.8610 


20 


50 


0JI27 


.6539 


J)I55 


7566 


.8789 


.8642 


.9366 


1.1571 .0634 


0.6581 


to 


4P00' 


0.7156 


.6561 


9J)169 


7547 


9JJ778 


iM93 


9.9392 


1.1504 0.0606 


0.8552 


49* 00' 


10 


0.7185 


.6583 


w8I84 


7528 


.8767 


.8744 


.9417 


1.1436 0)583 


0.8523 


50 


20 


0.7214 


.6604 


.8198 


7S09 


J756 


.8796 


.9443 


1.1369 .0557 


0.8494 


40 


30 


0.7243 


.6626 


.8213 


.7490 


.8745 


.8847 


.7700 


1.1303 .0532 


0.8465 


30 


40 


0.7272 


.6648 


.8227 


7470 


.8733 


.8899 


WJAJ 


1.1237 .0506 


0.8436 


20 


50 


0.7301 


.6670 


JU41 


7451 


jan 


.8952 


.9519 


1.1171 0)481 


0.8407 


10 


42*00' 


0.7330 


.6691 


9.8255 


7431 


9.8711 


.9004 


9.9544 


1.1106 a0456 


0.6378 


48* QC 


10 


0.7359 


.6713 


.8269 


7412 


J)699 


.9057 


.9570 


1.1041 .0430 


0.6348 


SO 


20 


0.7389 


.6734 


.8283 


7392 


^oOOo 


.9110 


.9595 


1.0977 0HO5 


0.8319 


40 


30 


0.7418 


.6756 


.8297 


7373 


.8676 


.9163 


.9621 


1.0913 J6379 


00)290 


30 


40 


0.7447 


.6777 


jaw 


.7353 


il665 


.9217 


.9646 


1.0850 .0354 


0.8261 


20 


50 


0.7476 


.6799 


.8324 


7333 


J653 


.9271 


.9671 


1.0786 0)329 


a8232 


10 


o^oy 


0.7505 


.6820 


9.8338 


.7314 


9.8641 


.9325 


9.9697 


1.0724 0.0303 


0.8203 


4I»00' 


10 


0.7534 


.6841 


.8351 


7294 


i)629 


.9380 


.9722 


1.0661 .0278 


0.8174 


SO 


20 


0.7563 


.6862 


.8365 


.7274 


J)618 


.9435 


.9747 


1.0599 0)253 


0.8145 


40 


30 


07592 


.68B4 


.8378 


.7254 


8606 


.9490 


• .9772 


1.0536 0)226 


0.6116 


30 


40 


0.7621 


.6905 


J)391 


7234 


0)594 


.9545 


.9798 


1.0477 .0202 


0.8087 


20 


50 


0.7650 


.6926 


J405 


.7214 


.8582 


.9601 


.9623 


1.0416 0)177 


a6056 


10 


44*00' 


0.7679 


.6947 


9.8418 


7193 


9.8569 


.9657 


9.9848 


1.0355 0.0152 


0.6029 


46*00' 


10 


0.7709 


.6967 


.8431 


7173 


.8557 


.9713 


.9874 


1.0295 .0126 


0.7999 


SO 


20 


0.7738 


.6988 


HAAA 


7153 


.8545 


.9770 


OAQO 


1.0235 .0101 


0.7970 


40 


30 


0.7767 


J009 


.8457 


7133 


.8532 


.9827 


.9924 


1.0176 .0076 


0.7941 


30 


40 


0.7796 


.7030 


.O^Ot 


.7112 


J8520 


.9Bo4 


OQJO 


1.0117 .0051 


07912 


20 


50 


0.7825 


.7050 


.8482 


7092 


.8507 


.9942 


.9975 


10)058 0)025 


07883 


10 


45»00' 


0.7854 


.7071 


9.8495 


.7071 


9.8495 


1.0000 


0.0000 


10)000 0.0000 


0.7854 


4S>00^ 






Nat. 


Log.' 


Nat. 


Log.' 


Nat. 


Log.' 


Nat. Log. 










Cosines 


Rinss 




Tangents 


Ra- 
dians 


Do- 



MATHEMATICAL TABLSfi 



11 



DICIICAL BQUIVALUITS 



from mmiitw and 
•eoondi into deci- 
mal Darts of a 
degree 



ir 



ly 



9r OPjOOOO 

J)I67 

J033 

J» 

iM7 

J»3 

.10 

.1167 

.1333 

.15 

VAda 
.1833 
JO 
Jt67 
J333 
JS 
MO 
.2833 
JO 
31^ 

0*3333 
35 
36C7 
3833 
.40 

.41671 
.4333 
.45 
.4M7 
.4633 

QP30 
3167 
3333 
35 
3667 
3833 
.60 
.6167 
.6333 
.65 

0^.6667 
.6833 
JO 
J167 
.7333 
J5 
J667 
J833 
JO 
JI67 

V»J333 
M 
.8667 
J833 
.90 
.9167 
.9333 
.95 
.96C7 
.9033 

IjOO 



3y 



W 



» 



or 

I 

2 
3 

4 

y 

6 
7 
8 

9 
W 

I 

2 

3 

4 
15* 

6 

7 

8 

9 



I 
2 
3 
4 

25* 
6 
7 
8 
9 



I 
2 
3 
4 

35* 
6 
7 
8 
9 

4ar 

I 

2 

3 

4 

45* 

6 
7 

8 
9 



I 
2 
3 
4 

55* 
6 
7 
8 
9 



0^.0000 
.0003 
il006 

xoos 

JOOII 
J00I4 
M}7 
M}9 
.W22 
.0025 

OP.0028 
.0031 
.0033 
J0036 
J0039 
JM2 
j0044 
X)047 
J05 
.0053 

O'.0056 
.0058 
J006I 
J0064 
J0067 
J0069 

Ja075 
.0078 
.0081 
O^J0083 
.0086 



.0092 

.0094 

J0097 

M 

J0IO3 

.0106 

iMOO 

VJ0I11 
.0114 
.0117 
ill 19 
.0122 
JN25 
J0I28 
4^131 
i)t33 
i)l36 

0»4>I39 
J0I42 
.0144 
ill47 
ill5 
.0153 
J0I56 
J>IS8 
.0161 
.DIM 

0^.0167 



From decimal parts of 


a degree into minutes 


and seoonds (exact 


▼aiues) 




0P.OO 


c 


0^.80 


30' 




V w 




30' 36* 




V \v 




31' \r 




V 48" 




31' 48* 




V W 




32' 24* 


0»il5 


y 


0»35 


33' 




y yf 




33' 36* 




V \v 




34' 12* 




¥ 48' 




34' 48* 




y w 




35' 24* 


r.io 


a 


0<'.6O 


36' 




v w 




36' 36* 




r \v 




37' 12' 




r 48* 




37' 48' 




y 24* 




38' 24' 


0».15 


y 


0^.65 


yr 




y 36* 




yr w 




10' 12* 




40' 12* 




10* 48' 




40' 48' 


^% 


ir 24* 




41' 24* 


rjo 


12' 


0».T0 


42' 




12' 36* 




Ar W 




\y w 




4y 12* 




13' 48' 




43' 48' 




14' 24* 




44' 24* 


trjs 


15' 


0°75 


45* 




15' W 




45' 36* 




W 12' 




46' 12' 




16' 48' 




46' 48' 




17' 24* 




47' 24' 


r.8o 


18' 


VM 


48' 




18' 36* 




4r 36* 




19' 12' 




49' 12' 




\y 48' 




49* 48' 




20' 24^ 




50' 24* 


0^35 


21' 


0»J5 


51' 




21' 36* 




51' 36* 




22* 12* 




52' 12' 




ir 48' 




5r 48' 




23* 24* 




5y 24* 


0P.4O 


24' 


OP.OO 


54' 




24^ 36* 




54' 36* 




25' 12' 




55' 12* 




25' 48' 




W W 




26^ TAf 




^ W 


0».45 


27' 


0°.95 


57' 




27' 36* 




57' 36* 




28' 12* 




58' 12' 




28' 48' 




58' 48' 




29* 24^ 




59' 24* 


r.io 


30' 


1<>.00 


60' 


0>.000 


O'.O 




1 


3'.6 






7'.2 






10'.8 






14'.4 




00.005 


18' 






21'.6 






25'.2 






28'J 






3r.4 




0*.010 


36' 





Common fractions 


8 16 
ths ths 


32 
nds 


64 
ths 


Exact 

decimal 

values 






1 


.01 562S 






2 


.03 125 






3 


.04 6875 


1 




4 


.06 25 






5 


.07 8125 






6 


J»375 






7 


.10 9375 


1 2 




8 


.12 5 






9 


.14 0625 






10 


.15 625- 






II 


.17 1875 


3 




12 


.18 75 






13 


.20 3125 






14 


1\ 875 






15 


.23 4375 


2 4 




16 


.25 






17 


.26 5625 






18 


.28 125 






19 


J9 6875 


5 




20 


31 25 






21 


.32 8125 






22 


.34 375 






23 


.35 9375 


3 6 




24 


.37 5 






25 


.39 0625 






26 


.40 625 






27 


.42 1875 


7 




28 


.43 75 






29 


.45 3125 






30 


.46 875 






31 


.48 4375 


4 8 




32 


.50 






33 


31 5625 






34 


33 125 






35 


34 6875 


9 




36 


36 25 






37 


.57 8125 


\ 




38 


.59 375 






39 


.60 9375 


5 10 




40 


.62 5 






41 


.64 0625 






42 


.65 625 






43 


.67 1875 


II 


22 


44 


.68 75 






45 


JO 3125 




•n 


46 


71 875 






47 


J3 4375 


6 12 


24 


48 


J5 






49 


76 5625 




25 


50 


78125 






51 


.79 6875 


13 


26 


52 


Xi 25 






53 


.82 8125 




27 


54 


J4 375 






55 


015 9375 


7 14 


28 


56 


.87 5 






57 


.89 0625 




29 


58 


.90 625 






59 


.92 1875 


13 


30 


60 


.93 75 






61 


.95 3125 




31 


62 


.96 875 






63 


.98 4375 



12 MATflESfATICAL TAHLRR 

s 

CIBCUMrBRBNCXS AND ABBAS OF GIBCLS8 BT BIQBTHS, BTO. 



• 


• 

a 


< 


• 

3 


• 

"2.749 


2 

< 


• 


• 

1 

h 


J 


• 

s 

s 


• 

6 


< 








H 


.6013 


4 


1157 


1157 





28.27 


63.62 


\u 


.04909 


.00019 


•Hi 


1798 


.6230 


He 


1176 


1196 


1^ 


28.67 


65.40 


Ha 


.09617 


.00077 


•Ha 


2.847 


.6450 


H 


1196 


1336 


^ 


29.06 


67.20 


H4 


.1473 


.00173 


•Hi 


1896 


.6675 


He 


13.16 


13.77 


H 


29.45 


69j03 


Ht 


.1963 


.00307 


»M« 


1945 


.6903 


H 


13.35 


14.19 


H 


29.65 


70.88 


«4 


.2454 


.00479 


•Hi 


1994 


.7135 


Me 


13.55 


14.61 


f^ 


30.24 


7276 


ii 


J945 


.00690 


•Ha 


3.043 


7371 


H 


1374 


15.03 


H 


30.63 


74.66 


?^ 


3436 


.00940 


•Hi 


3.093 


7610 


He 


13.94 


15.47 


H 


3IJ02 


7639 


H 


.3927 


.01227 


1 


3.142 


.7854 


H 


14.14 


15.90 


10 


31.42 


7834 


Hi 


.4418 


.01553 


Me 


3336 


.8866 


Me 


14.33 


16.35 


H 


31.61 


8032 


Ha 


.4909 


.01917 


H 


3.534 


.9940 


H 


1433 


16.80 


H 


3120 


6232 


'H4 


3400 


.02320 


He 


3.731 


1.108 


»He 


1473 


1776 


H 


3239 


64.54 


Mt 


3890 


.02761 


H 


3.927 


1.227 


H 


14.92 


17.72 


H 


32.99 


86.59 


'H« 


.6381 


.03241 


Me 


4.123 


1.353 


>He 


15.12 


16.19 


H 


3336 


86.66 


Ha 


.6872 


.03758 


H 


4.320 


1.485 


H ' 


15.32 


16.67 


H 


3377 


9076 


iH« 


.7363 


XH314 


He 


4316 


1.623 


*Me 


1531 


19.15 


H 


34.16 


97.89 


H 


.7854 


.04909 


H 


4.712 


1.767 


5 


1571 


19.63 


11 


34.56 


95.03 


>H4 


.8345 


.05542 


91e 


4.909 


1.917 


He 


15.90 


20.13 


H 


34.95 


9771 


Ha 


.8836 


.06213 


H 


5.105 


1074 


H 


16.10 


20.63 


H 


3534 


99.40 


»H4 


.9327 


.06922 


»Me 


5301 


1237 


He 


1630 


21.14 


H 


3574 


101.6 


M6 


.9617 


.07670 


H 


5.498 


1405 


H 


16.49 


21.65 


H 


36.13 


103.9 


*H4 


1.031 


.06456 


»Me 


5.694 


1580 


Me 


16.69 


22.17 


IJ 


3632 


106.1 


iHa 


1.060 


.09281 


H 


5.890 


1761 


H 


\bm 


2169 


36.91 


106.4 


»>i4 


1.129 


.1014 


»Mc 


6.087 


1948 


He 


MM 


23.22 


H 


3731 


110.8 


•H 


1.178 


.1104 


% 


6.283 


3.142 


H 


17.28 


23.76 


11 


37.70 


113.1 


*H4 


1.227 


.1196 


Me 


6.480 


3.341 


Me 


17.48 


24.30 


H 


36i)9 


1153 


>Ha 


1.276 


.1296 


Vi 


6.676 


3.547 


H 


17.67 


24.65 


H 


36.46 


117.9 


•^i* 


1325 


.1396 


He 


6.872 


3.758 


»Me 


17.87 


25.41 


H 


36J6 


1203 


ni 


1.374 


.1503 


M 


7.069 


3.976 


H 


18.06 


25.97 


H 


39.27 


1227 


1.424 


.1613 


Me 


7.265 


4.200 


•Me 


1876 


26.53 


H 


39.66 


1257 


»H2 


1.473 


.1726 


H 


7.461 


4.430 


H 


18.46 


27.11 


H 


40i)6 


1277 


»H« 


1322 


.1843 


He 


7.658 


4.666 


»Me 


16.65 


27.69 


H 


4a45 


1307 


H 


1.571 


.1963 


H 


7.854 


4.909 


< 


16.85 


28.27 


IS 


40.64 


1317 


•H4 

»Ha 

•H4 


1.620 


.2088 


Me 


8.050 


5.157 


H 


19.24 


29.46 


H 


4173 


1353 


1.669 


.2217 


H 


8.247 


5.412 


H 


19.63 


30.66 


H 


41.63 


137.9 


1718 


J349 


>Me 


6.443 


5.673 


H 


20.03 


31.92 


H 


A2Sa 


1403 


91a 


1.767 


.2485 


H 


6.639 


5.940 


H 


20.42 


33.16 


H 


4141 


143.1 


•Hi 


1.816 


.2625 


»Me 


8.836 


6.213 


H 


20.81 


34.47 


H 


4180 


145.8 


»Ha 


1.865 


.2769 


H 


9.032 


6.492 


H 


2171 


35.76 


H 


4370 


1463 


•Hi 


1.914 


J9I6 


»Me 


9.228 


6.777 


H 


21.60 


37.12 


H 


4339 


1517 


H 


1.963 


.3068 


S 


9.425 


7.069 


7 


21.99 


36.46 


14 


43.96 


153.9 


*Hi 


2.013 


.3223 


Me 


9.621 


7.366 


H 


2136 


39.87 


H 


4437 


1567 


•Ha 


2.062 


.3382 


H 


9.817 


7.670 


H 


22.78 


41.28 


H 


44.77 


1593 


*5^ 


1111 


.3545 


He 


10.01 


7.980 


H 


23.17 


4172 


H 


45.16 


1623 


>H« 


2.160 


3712 


H 


10.21 


8.296 


H 


23.56 


44.18 


H 


4535 


165.1 


i^ 


1209 


.3883 


Me 


10.41 


8.618 


H 


23.95 


45.66 


H 


45.95 


168.0 


2.258 


.4057 


H 


10.60 


8.946 


H 


24.35 


47.17 




46.34 


170.9 


*Hi 


1307 


.4236 


He 


10.80 


9781 


H 


2474 


46.71 


H 


46.73 


173^ 


H 


1356 


.4418 


H 


11.00 


9.621 


8 


25.13 


50.27 


IS 


47.12 


1767 


*Hi 


1405 


.4604 


Me 


11.19 


9.966 


H 


2533 


51.65 


H 


4732 


1797 


•Ha 


1454 


.4794 


H 


11.39 


10.32 


H 


25.92 


53.46 


H 


47.91 


1617 


•Hi 


1503 


.4987 


»Me 


1136 


10.68 


H 


2631 


55.09 


H 


4630 


1857 


Iff, 


1553 


3185 


H 


11.78 


11.04 


H 


26.70 


56.75 


n 


46.69 


1867 


^Hi 


1602 


3386 


iMe 


11.98 


11.42 


H 


27.10 


56.43 


49.09 


1917 


a^f 


1651 


3591 


H 


1117 


11.79 


27.49 


60.13 


H 


49.46 


194.6 


•Hi 


1700 


.5800 


^^e 


1137 


1118 


J* 


27.88 


61.66 


H 


49.87 


197.9 



MATHEMATICAL TABLES 



13 



CIRCU1SFKRBNCS8 AND AREAS BT XIOHTH8— (eon(»nti«d} 



• 

s 

5 


• 

3 


J 


• 

5 


• 

1 


1 


• 

a 

e 

a 


• 

a 
1 


(0 

1 


a 


• 

a 
5 


2 

-< 


li 


S0J7 


201.1 


l»H 


6176 


298.6 


IS 


7276 


4153 


M 


91.11 


6603 


H 


50^ 


204a 


H 


61.65 


3023 


H 


72.65 


420 J) 


i 


9139 


672j0 


H 


51JQ5 


207.4 


M 


62.05 


306.4 


H 


73i>4 


424.6 


i 

H 


92.68 


6833 


H 


51.44 


2ro.6 


H 


62.44 


3107 


H 


73.43 


429.1 


93.46 


695.1 


H 


SIM 


213^ 


10 


6283 


3147 


1^ 


73.83 


4337 


80 


9475 


706.9 


H 


5i» 


217.1 


H 


63.22 


318.1 


M 


74.22 


438.4 


H 


95.03 


7187 


K 


52^ 


220.4 


H 


63.62 


322.1 


H 


74.61 


443.0 


H 


95.82 


730A 


H 


53il1 


223.7 


H 


64m 


326.1 


H 


75i)l 


4477 


H 


96l60 


742j6 


17 


53^1 


WA 


H 


64.40 


330.1 


M 


75.40 


452.4 


81 


97.39 


754J 


H 


53J0 


2303 




64.80 


334.1 


}i 


76.18 


461.9 


H 


98.17 


767.0 


K 


54.19 


233J 


^ 


65.19 


3387 


\i 


76.97 


471.4 


H 


98.96 


7793 


H 


5159 


237.1 


H 


6538 


3427 


H 


77J5 


481.1 


H 


9975 


7917 


H 


54.98 


2403 


tl 


65.97 


346.4 


U 


7834 


490.9 


n 


1003 


8047 


^ 


55J7 


244.0 


H 


6637 


3503 


H 


7933 


5007 


^ 


I0I3 


816.9 


5576 


247.4 


H 


66.76 


3547 


Vi 


80.11 


5107 


H 


102.1 


829j6 


H 


56.16 


250.9 


H 


67.15 


358J 


H 


80.90 


520.8 


102.9 


8414 


18 


5635 


2543 


H 


67.54 


363.1 


18 


81.68 


530.9 


88 


1037 


8553 


H 


56u94 


258JI 


H 


67.94 


3673 


H 


82.47 


5417 
5513 


H 


1043 


8683 


H 


5733 


261.6 


H 


6833 


3713 


H 


8375 


^ 


1057 


881.4 


H 


5773 


265J 


H 


68.72 


375.8 


H 


84.04 


562J) 


106J) 


894.6 


>i 


58.12 


268^ 


t% 


69.12 


380.1 


17 


8432 


572.6 


U 


\QU 


907.9 




5831 


2714 


H 


6931 


3843 


H 


85.61 


5837 


H 


107.6 


9213 


^ 


58.90 


276.1 


M 


69.90 


388.8 


H 


86.39 


594.0 




108.4 


934.8 


H 


59J0 


279.8 


H 


7079 


3937 


H 


87.18 


604.8 


1097 


948.4 


If 


59^ 


2833 


h 


70.69 


397.6 


U 


87.96 


615.8 


85 


110.0 


962.1 


>i 


6OJ06 


2873 


H 


7Ij08 


402.0 


u 


8875 


626.8 


n 


1107 


975.9 


H 


60.48 


291 i) 


H 


71.47 


406.5 


w 


8934 


637.9 


1113 


9e9JB 


H 


60J7 


2940) 


H 


71.86 


411.0 


H 


90.32 


6497 


H 


1123 


1003.8 



A&XAS OF CntCLES. 


DiMneters in Feet and Inohet, Areas in Square Feet 


Feet 


Inches 




1 


23456 789 10 M 






JOOOO 


.0055 


.0218 


.0491 


.0873 


.1364 


.1963 


7673 


3491 


.4418 


3454 


.6600 


1 


7854 


.9218 


\M9 


1727 


13% 


1.576 


1767 


l.%9 


2.182 


2.405 


2.640 


2.885 


2 


3.142 


3.409 


3.687 


3.976 


4776 


4387 


4.909 


5741 


5.585 


5.940 


6305 


6.681 


3 


7jm 


7.467 


7376 


8796 


8727 


9.168 


9.621 


10.08 


10.56 


11.04 


11.54 


12.05 


4 


1237 


13.10 


I3j64 


14.19 


1475 


1532 


15.90 


1630 


17.10 


1772 


1835 


18.99 


5 


19.63 


2079 


20.97 


2165 


2234 


23.04 


23.76 


24.48 


2572 


25.97 


2673 


27.49 


^ 6 


2877 


29.07 


2937 


30.66 


31.50 


3234 


33.18 


34.04 


34.91 


35.78 


36.67 


3737 


7 


38.48 


39.41 


4034 


4178 


4274 


4370 


44.18 


45.17 


46.16 


47.17 


48.19 


4972 


8 


5077 


5132 


5238 


53.46 


5434 


5534 


5675 


5736 


58.99 


60.13 


6178 


62.44 


9 


63.62 


64JB0 


66.00 


6770 


68.42 


6934 


7038 


72.13 


7339 


74j66 


75.94 


7774 


10 


7834 


7935 


81.18 


8232 


8336 


8572 


8639 


87.97 


8936 


90.76 


92.18 


93.60 


11 


95.03 


96.48 


97.93 


99.40 


100.9 


102.4 


103.9 


105.4 


106.9 


108.4 


110.0 


1113 


12 


113.1 


1147 


1163 


117.9 


1193 


121.1 


1227 


124.4 


126X) 


1277 


129.4 


131J0 


13 


1327 


134.4 


1367 


137.9 


139.6 


141.4 


143.1 


144.9 


1467 


1483 


1503 


1511 


14 


153.9 


1553 


157 j6 


1593 


161.4 


1637 


165.1 


167.0 


168.9 


170.9 


1723 


1743 



From Inches and Fractions of an Inch to Decimals of a Foot 



lochea 
Feet 



1 
.0833 



2 

.1667 



3 
.2500 



4 
.3333 



6 
.4167 



6 
.5000 



7 
5833 



8 
6667 



9 
7600 



10 
8333 



11 
.9167 



Inches H H H \^ H 94 H 

Feet .0104 .0208 .0313 .0417 .0521 .0625 .0729 

■zample. 6 ft. 7H in. - 5.0 + 0.5833 + 0.0313 - 6.6146 ft. 



14 



MATHBMATTCAL TABLES 



ConTenion TaJt>l«i 

All measiiree of length, area, and cubic measures in the following tables 
are derived from the international meter. The metric system of weights 
and measures was legalised and its use made permissive in the United States 
by an Act of Cons^ess, passed in 1866. In 1891, the Office of Weights and 
Measures (now Bureau of Standards) fixed the value of the United States 
yard in terms of the international meter, as follows: 1 yard » 8600/8987 
meters. At the same time, the pound was fixed in terms of the inter- 
national kilogram, as follows: 1 pound « 468.50143 graniB. Measures 
of capacity are based on the following relations: 1 cubic decimeter « 
1 liter ; 1 U. 8. gallon » tSl cu. in. ; 1 Imperial gallon (Britigh) « 277.418 
cu. in. A liter is the volume occupied by 1 kilogram of water under a 
pressure of 76 cm. of mercury and at a temperature of 4 deg. C. 

By itandard locality is meant any locality where ac "» 980.665 cm. 
per sec. per sec, or 32.1740 ft. per sec. per sec. This value, g^, is assumed 
to be the value of g at sea level and latitude 45 deg.. and is called standard 
gravity. 

Acceleration of Oravity 

(U. S. Coast and Geodetic Survey, 1912) 



Latitude, 





o/q^ 


Latitude, 
deg. 





o/o* 


dec. 


Cm./eeo.' 


Ft./eec.' 


Cm./eec* 


Ft./Beo.» 




10 

20 

»30 

40 


978.0 
978.2 
978.6 
979.3 
960.2 


32.088 
32.093 
32.106 
32.130 
32.158 


0.0973 
0.9975 
0.9979 
0.9966 
0.9995 


50 
60 
70 
80 
90 


981.1 
981.9 
962.6 
983.1 
963.2 


32.187 
32.215 
32.238 
32.253 
32.258 


1.0004 
1.0013 
1.0020 
1.0024 
1.0026 



Correction for altitude above ma level:— 0.3 cm. i>er aeo.* for each 1000 meters, 
-0.003 ft. per sec.* for each 1000 feet . 



Force EqulTalenta 



Dvnea X 10* 


1 

1.020 
0.00648 

2.248 
0.03518 

72.33 
1.8fi033 


0.9807 
1.09149 

1 

2.205 
0.34334 

70.93 
1.85084 


0.4446 
1.64819 

0.4536 
1.85867 

1 

32.17 
1.50750 


0.01383 


Kilograma. 


2.14067 
0.01410 


Pounds. 


2.14016 
0.03106 


Poundals 


2.49249 
1 







MATHEMATICAL TABLES 



15 



Lenrth BquiTalentf 



Ctttimeien 


Incbet 


Feet 


Yanlfl 


Meters 


ChaiDB 


Kilometen 


MUeei 


1 


0.3937 
r.50617 


0.09281 
f.51598 


0.01094 

F.03886 


0.01 
S: 00000 


0.0«4971 
r.60644 


10-i 

rooooo 


0.0i6214 
6.79385 


2.540 

0.4048S 


1 


0.0t6333 
4.92082 


0.02778 
7.44370 


0.0254 

r.40483 


0.0«1263 
5.10127 


0.0i254 

5.40488 


0.0«1578 
5:19618 


30.46 
1.48402 


12 
1.07918 


1 


0.3333 
r.62288 


0.3046 

r.484Q8 


0.01515 
2.18046 


0.0i3096 

7.48402 


0.0il645 
r.21608 


91.14 
1.96114 


36 
1.55630 


3 

0.47712 


1 


0.9144 
r.96114 


0.04545 
J". 65758 


0.0s9144 
r.96114 


0.0i5682 
4.75448 


100 

s.ooooo 


39.37 
1.50517 


3.281 
0.51598 


1.0936 
0.03886 


1 


0.04971 
2'.60644 


0.001 
8.G0O0O 


0.0i62l4 
r79886 


2012 
8.80666 


792 

2.80673 


66 
1.81964 


22 
1.34242 


20.12 
1.30356 


1 


0.02012 
2:30856 


0.0125 
7.09601 


lOOOOO 
6.00OOO 


39370 
4.50617 


3281 
8.51596 


1093.6 
3.08886 


1000 
3.00000 


49.71 
1.89644 


1 


0.6214 
r.79336 


160925 
6.80666 


633M 
4.80182 


5280 
8.72208 


1760 
8.24551 


1609 
3.80666 


80 
1.90809 


1.609 
0.20665 


1 



> One Nftutioal mfle <- 6080.2 feet. 



Area BquiTalents 



8<fu&re 
oentimeters 


Square 
meters 


Square 
inches* 


Square 
feet 


Sqaure 
yards 


Square 
miles 


1 


0.0001 


0.155 
1.19038 


0.001076 
T. 03197 


0.0001196 
4.077r3 


0.0i«3861 
11.58670 


10.000 
4.0O00O 


1 


1550 
8.10J83 


10.76 
1.03197 


1.196 
0.077r3 


0.0t3861 

T58670 


6.452 
0.80967 


0.0^52 
4.80067 


1 


0.006944 
T.84164 


0.0011 
i:04139 


0.0^491 
10.39637 


929 
2.96803 


0.0929 
T.96803 


144 
2.15886 


1 


o.ini 

T.04576 


0.073587 

8.55473 


8361 


0.8361 


1296 ' 


9 


1 


0.0i3228 


80.2227 


T.92227 


3.11200 


0.95424'> 




7.50898 




2589|8 
6.41830 




27878400 
7.44527 


3097600 
6.49102 


1 


• 10» 


10* 




10764100 


1196011 


0.3661 








7.03197 


6.07773 


1.58670 



iQne circular mil - area of circle 0.001 in. in diam. 1,000,000 cir. mils - 1 dr. in. 

The equivalents are given in the heavier type. Logarithms of the equivalents are 
given immediately below. 

Subecripta after any figure. Da, 94, eto., mean that that figure is to be repeated the 
indicated number of tmui. 



16 



MATHEMATICAL TABLES 



Volume and Capacity SquiTalents 



Cubic 
inobes 



Cubic 
feet 



Cubic 
yuds 



Cubic 
centi- 
meters 



Cubic 
meters 



U. S. liquid mens- 
ure 



Quarts i GaQons 



Liters 



1 


0.0a5787 
4.76246 


0.0i2l43 
3T33100 


16.387 
1.21450 


0.0il6387 
5.21450 


0.01732 
2.23845 


0.0i4329 
1763630 


0.01639 
2.21450 


1728 
3.23754 


1 


0.03704 
T56864 


28317 
4.45205 


0.028317 
2.45205 


29.92 
1.47500 


7.481 
0.87303 


28. 3« 
1.45205 


46656 

4.66801 


27 

1.43136 


1 


764557 

5.88341 


0.764557 
1.88341 


807.9 
2.00736 


202.0 
2.30530 


• 764.6 
2.88341 


0^061 : 
2:>8550 


0.0t353 
5.54706 


0.0il306 
6.11661 


1 


io-« 


0.001057 
3.02304 


0.0»2642 
4.42188 


0.001 


61024 
4.78550 


35.315 
1.54706 


1.306 
0.11661 


10« 


1 


1057 
3.02304 


264.2 
3.42188 


1000 


. 57.75 
1.76155 


0.03342 
2.52401 


0.001238 
3.00264 


946.3 
2.07580 


0.000946 
4.07580 


1 


0.25 
1.30704 


0.9464 
1.07606 


231 

2.36361 


0.1337 
1.12607 


0.004951 

3.60470 


3785 

3.57807 


0.0003785 
4.57807 


4 
0.60206 


1 


3.785 

0.57812 


61.02 
1.78550 


0.03531 
2.54705 


0.001306 
3.11650 


1000 


0.001 


1.057 

0.02304 


0.2642 
1.42188 


1 



Velocity IquiTalcnts 



Centimeters 
per sec. 


Meters 
per sec. 


Meters 
per min. 


Kilo- 
meters 
per hour 


Feet 
per sec 


Feet 
per min. 


Miles 
per hour 


Knots 


1 


0.01 


0.6 
r.77815 


0.036 

2.55630 


0.03281 
2.51508 


1.9685 
0.80414 


0.02237 
2.34065 


0.01942 

7.28825 


100 
2.00000 


1 


60 

1.77815 


3.6 

0.55630 


3.281 
0.51508 


196.65 
2.29414 


2.237 
0.34065 


1.942 
0.28825 


1.667 
0.22184 


0.01667 

2122184 


1 


0.06 

5". 77815 - 


0,05468 

2.73783 


3.281 
0.61696 


0.XK3728 

r. 57150 


0.03237 

7.51018 


27.78 
1.44370 


0.2778 
T.44370 


16.67 
1.22184 


1 


0.9113 
T. 05068 


54.68 
1.73783 


0.6214 
T. 70335 


0.53960 
r. 73207 


30.48 
1.48402 


0.3048 

r.48402 


18.29 
1.26217 


1.097 
0.04032 


1 


60 
1.77815 


0.6818 
1.83367 


0.59209 
r 77238 


0.5060 

1.7C586 


0.005060 

r. 70586 


0.3048 

r.48402 


0.01829 
2:26217 


0.01667 
7.22185 


1 


0.01136 
7.05553 


0009«7 
7.00423 


44.70 
1.65035 


0.4470 
r. 65035 


26.82 

1.42850 


1.609 

0.20670 


1.467 
0.16633 


88 

1.94448 


1 


86839 
r0887l 


51.497 
1.71178 


51497 

r.71178 


30.898 
1.48003 


1.8532 
0.26703 


1.68894 
0.22761 


101.537 

2Mn 


1 15155 

06128 


1 



^ The equivalents are given in the heavier type. TjOgarithms of the equivalents an 
given immediately below. 

Subscripts after an^ figure, 0», O4, etc., mean that that figure is to be repeated thi 
indicated number of times. 



MATHEMATICAL TABLES 



17 



Mass Bquivalenta 





Grains 


Ounces 


Pounds 


Tons 


Kilograms 


Troy and 
apoth. 


Avoir- 
dupois 


Troy and 
apoth. 


Avoir- 
dupois 


Short 


Long 


Metric 


1 


15432 
4.18843 


32.15 

1.50719 


35.27 
1.54745 


2.6792 
0.42801 


2.205 

0.34338 


O.O1IIO2 
7.04230 


00i9642 
4.99309 


0.001 

7.00000 


O.Oi6480 

"5.81157 


1 


0.0i2063 
3.31876 


0.0i2286 

T.35902 


0.0«1736 

4.23058 


0.0il429 
4.15490 


O.O77143 

7.85387 


0.0t6376 
8.80465 


0.0i6460 
7.81157 


0.03110 
2.49281 


460 
2.68124 


1 


1.09714 
0.04026 


0.06333 

7.02082 


0.06857 
7.83614 - 


0.043429 
5.53511 


O.O4IO6I 
5.48590 


O.O43IIO 
7.49281 


0.02835 
7.45255 


437.5 
2.64008 


0.9115 
1.95974 


1 


0.07595 
X88056 


0.0625 
7.79688 


O.O43125 
5.49485 


0.042790 
5.44563 


0.042835 
7.45255 


0.3732 

1^7199 


5760 

3.76042 


12 

1.07918 


13.17 

1.11944 


1 


0.6229 
T.91532 


0.0i4114 
4.61429 


0.0i3673 
4.56508 


0.0t3732 
4.57199 


0.4536 
1.66667 


7600 

3.84510 


14.58 

}. 16886 


16 

1.20412 


1.215 
0.08468 


1 


0.0005 

4.69897 


0.0i4464 
4.64975 


0.0a4536 
4.65667 


907.2 
2.06770 


140« 
7.14613 


29167 
4.46480 


320i 
4,50515 


2431 

3.38571 


2000 

3.30103 


1 


0.8929 
T.96078 


0.9072 
r.95770 


1016 
3.00691 


156804 
7.19535 


326« 

4.51411 


35640 
4.55437 


2722 

3.43492 


2240 
3.35025 


1.12 
0.04922 


1 


1.016 
0.00601 


1000 
3.00000 


15432356 
7.18843 


32151 
4.60719 


35274 
4.54745 


2679 
8.42801 


2205 
3.34338 


1.102 
0.04230 


0.9642 
T.908O9 


1 



ProiBure BqulTalonti 



Megabars 

or 
megadynes 

per 


Kilo- 
crams 

per 
SQ. om. 
(Metric 
atmos- 
pheres) 


Pounds 

per 
sq. m. 


Short 
tons 
per 

sq.ft. 


Atmos- 
pheres 


Columns of 
mercury at 
temperature 
iBdeg. C. 


Columns of water at 
temperature 15 deg. C. 


sq. om. 


Meters 


Inches 


Meters 


Inches 


Feet 


1 

0.9607 
t. 99152 

0.06895 
2.83853 

0.9576 ' 
r.96119 

1.0133 
0.00578 

1.3333 
0.12493 

0.03366 
7.62075 

0.09796 
7.99114 

0.002489 
3.39696 

0.02966 
747516 


1.0197 
0.00848 

1 

0.07031 

784700 

0.9765 
r.06966 

1.0333 
0.01421 

1.3596 
0.13340 

0.03453 

7.53823 

0.09991 
799068 

0002538 
3.40446 

0.03045 
748364 


14.50 
1.16148 

14.22 
1.15300 

1 

13.69 
1.14267 

14.70 

1.16722 

19.34 
1.38640 

0.4912 
r.69124 

1.421 
0.15262 

0.03610 
2.55746 

0.4332 
r.63664 


1.044 
0.01882 

1.024 
0.01034 

0.072 
7.86733 

1 

1.056 
0.08955 

1.392 
0.14373 

0.03536 
754857 

0.1023 
r.00096 

0.002599 

741479 

0.03119 
749307 


0.9869 
r.99427 

0.9676 
r.98579 

0.06004 
783279 

0.9450 

r. 97545 

1 

1.316 

0.11919 

0.03342 
7.52402 

0.09670 
796641 

0.002456 
730024 

0.02947 
7.46942 


0.7500 

r.87508 

0.7355 

r.86660 

0.05171 
771360 

0.7182 
r.85627 

0.76 

r.88081 

1 

0.02540 
2.40484 

0.07349 
7.86622 

0.001867 
727106 

0.02240 
735024 


29.53 
1.47025 

26.96 

1.46177 

2.036 
0.30676 

26.26 
1.45143 

29.92 

1.47588 

39.37 
1.50517 

1 

2.893 
0.46139 

0.07349 

786622 

0.8819 
r.94540 


10.21 
1.00886 

10.01 
1.00038 

0.7037 

r.84738 

9.773 
0.09004 

10.34 
1.01459 

13.61 

1.13378 

0.3456' 
r. 53861 

1 

0.02540 

7.40484 

0.3048 
r.48402 


401.6 
2.60402 

394.0 
2.59555 

27.70 

1.44254 

364.6 

2.58521 

407.2 
2.60976 

535.7 

2.72804 

13.61 
1.13378 

39.37 
1.59517 

1 

12 

1.07018 


33.48 
1.52484 

32.64 
1.51636 

2.309 
0.36336 

32.06 
1.50608 

33.93 
1.58068 

44.64 
1.64976 

1.134 
0.05460 

3.261 
0.55198 

0.06333 

2.02082 

1 



The equivalents are given in the heavier type. Logarithms of the equivalents arc 
givMi immediatdy below. 

Subscripts after any figure, 0t» 94, etc., mean that that figure is to be repeated the 
indicated number of tunes. 



18 



MATHEMATICAL TABLES 







Eneigj 


' or Work Squiralents 








Joules « 
10' ergs 


KUocram- 
meters 


Fooi- 
pounda 


Kilo- 
wati- 
hours 


Ch«Tal- 

Tapenr- 

houn 


Horse- 

powBf- 

houra 


Uter- 

atmos- 

pheres 


KUo- 
Sram- 
calories 


British 

thennal 

tinita 


1 


0.10197 

r.00848 


0.7376 
r.86780 


O.Oi2778 

r.44870 


0.0«3777 

T.67711 


0.0*3n5 

T:6ni3 


0.009069 
8:00427 


0.0*2390 

7:37848 


0.0^9406 

r.97700 


9.80665 
0.0015207 


1 


7.233 
0.85032 


0.0»2724 
6'.43622 


O.0«37037 
6'.66863 


0.0*3653 
^66265 


0.09676 
1:08670 


0.002344 
3:37000 


0009302 
r06861 


1.356 
0.1S220 


0.1383 
r.l4068 


1 


0.0*3766 
7.57600 


0.0*51306 

r. 70032 


0.0*50505 
7'.70333 


0.0133e 
r 12647 


0.0*3241 
4.51068 


0.001286 
3.10020 


3.6X 10« 
6.66630 


3.671XI0* 
6.66478 


2.655X10* 
6.42410 


1 


1.3596 
0.13342 


1.341 
0.12743 


35528 
4.56057 


860.5 
2.03478 


3415 


2.648X10* 
6.42288 


270000. 
6.43136 


1.9529X10* 
6.20068 


0.7355 
r86668 


1 


0.9063 
r.00401 


26131. 
4.41716 


632.9 
2.80135 


2512 • 
3.30006 


2.6845X10* 
6.42887 


2.7375X10* 
6.43736 


1 .96X 10* 
6.30667 


0.7457 
r.87257 


1.0139 
0.0060S 


1 


4.42314 


641.7 

2.80736 


2547 

3.40606 


101.33 
1.00673 


10.33) 
1.01431 


74.73 
1.87363 


0.0i28l5 
r.440tt 


0.0«3627 


0.0*3774. 

r57686 


1 


0.02422 
2.38425 


0,09612 


4183 
8.62163 


426.6 
2.63000 


3086 

3.48032 


0.001162 
§'.06622 


0.001580 
3.10864 


0.001556 

3.10266 


41.29 
1.61570 


1 


3.966 
0.60861 


1054 
3.02201 


107.5 
2.08139 


777.52 
2.80071 


0.0t2926 
r46661 


0.0.3961 
4760008 


0.0i3927 
7.60406 


10.40 
1.01710 


0.25200 
1.40130 


1 



Pow«r SqtiiTalentt 



Horse power 


KUo- 
watte 
(1000 
joules 
per see.) 


Cheral- 
vapeor 
(metrio 

ap.) 


Ponoe- 
lete 


M.-kg. 
per see. 


1 

Ft.-lbe. 
I>er sec. 


per see. 




560 stand- 
ard ft.-lb. 
per sec. 


B.t.tt 
per see. 


1 


0.7457 
r.87256 


1.014 
0.00500 


0.7604 
T.88105 


76.04 
1.88105 


550 

2.74036 


0.1783 
T.25104 


0.7074 

T.84065 


1.341 

0.12743 

0.9663 

T.00402 


1 

0.7355 

T.86660 


1.360 
0.13343 

1 


1.020 
0.00848 

0.75 
T.87606 


102.0 
2.00848 

75 
1.87506' 


737.6 

2.86780 

542.3 

2.73438 


0.2390 
T. 37848 

0.1756 
T.24506 


0.9466 
T.07700 

0.6977 
T 84367 


1.315 
0.11806 


0.9607 
T.90162 


1.333 
0.12403 


1 


100 
2.00000 


723.3 
2.85032 


0.2344 
T.37000 


0.9303 
T 06861 


0.01315 
T 11806 


0.009007 
T.09162 


0.01333 
T. 12403 


0.01 
T.OOOOO 


1 


7.233 
0.86032 


0.002344 

T.37000 


0.009303 
7.96861 


0.00182 
7.25046 


0.001356 
T 13210 


0.00184 
T 26562 


0.00136 
T. 14067 


0.1383 
T. 14067 


1 


0.0*3241 
T. 51068 


0.001286 
7.10020 


5.610 
0.74806 


4.163 
0.62153 


5.686 
0.75404 


4.266 
0.63000 


426.6 
2.63000 


3086 
3.48932 


1 


3.968 
0.50861 


1.414 
0.15035 


1.054 
0.02201 


1.433 
0.15632 


1.075 
0.03130 


107.5 
2.03130 


777.5 

2.80071 


0.2520 
T.40138 


1 



The equiyalento are given in the heavier type. Logarithms of the ^uivalente are 
given immediately below. 

Subaoripts aftor an^ figure, Os, 0«, etc., mean that that figure is to be repeated the 
indicated number of tmies. 



MATHBMATICAL TABLES 



19 



Doniity BquiTalonti and ConTonlon Fmctors 



EqiiiTalente 


Conversion factors 


Grame 
per ea. 
em. 


Lb. per 
cu. m. 


Lbe.per 
cu. ft. 


Short 
tons 

(2000 

lbs.) per 

eu. yd. 


Lba.per 

U. B. 

sal. 

• 




Grama 
per cu. 
em. to 
Ibe.per 
on. ft. 


Lb. per 
cu. It. 

per cu. 
cm. 


Grama 

per 
ou. cm. 
to short 
tons per 
ou. yd. 


Short 
tons per 

cu. yd. 

to grams 

per cu. 

cm. 


i 

27.68 

1.44217 

001602 
T.2M80 

1.186 
0.07428 

1198 
T07856 


0.03613 

T55787 

1 

O.Q»5787 
T.78S45 

0.04286 

T.83205 

0.004329 
7.83639 


62.43 
1.78639 

1728 
S.237M 

1 

74.07 

1.80064 

7.481 • 
0.87808 


0.8428 
T.9aS72 

23.33 
1.38798 

0.0135 
T 13083 

1 

•0.1010 
T.00432 


8.345 
0.02148 

231 
3.86361 

0.1337 
1.12813 

9.902 
0.09572 

1 


1 
2' 

10 


62.43 
124.90 

187.30 
249.70 

312.40 
374.60 

437.00 
499.40 

561.90 
624.30 


0.01602 
0.03204 

0.04806 
0.06407 

0.00009 
0.09611 

0.1 1210 
0.12820 

6.14420 
0.16020 


0.M28 
1.6860 

2.5280 
3.3710 

4.2140 
5.0570 

5.9000 

6.7420 

7.5850 
8.4280 


1.186 
2.373 

3.600 
4.746' 

5.933 
7.119 

8.306 

9.492 

10.680 
11.870 





Convonioii of Hoftt TrAnoiainioii u&d Oondttotlon 




Small 
calories 
per aq. 
em. to 

B.t.u. 

per eq. 

fL 


B.t.u. 

PM-sq. 

ft. to 

small 

calories 

per sq. 

cm. 


Small 

calories 

per sq. cm. 

per om. to 

B.t.u. per 

sq.ft. 

perm. 


B.t.u. 
per sq. ft. 
per in. to 

small 

calories |>er 

sq. cm. 

per om. 


Small ealoriee per 
sec. per sq. cm. 

per 1 doB> G. per 

em. tikiok, to B.t.u. 

per hr. per sq. ft. 
per 1 dec. F. 
per in. tmck 


B.t.u. per hr. per 
sq. ft. per 1 dec. 
F. per in. thick 
to small calories 
per sec. per sq. cm. 

per 1 des. C. 

per om. thiek 


1 


3.687 
7.374 
11.06 
14.75 

18.44 
22 12 
25 81 
29.50 

33.18 


0.2712 
0.5424 
0.8136 
1.085 

1.356 
1.627 
1.898 
2.170 
2.441 


1.451 
2.902 
4.353 
5.804 

7.255 
8.706 
10.16 
11.61 
13.06 


0.6892 
1.378 
2.068 
2.757 . 

3.446 
4.135 
4.824 
5.514 
6.2IB 


2.903X10* 

5.806X10* 

8.709X10* 

11.61 XI0> 

14.52X10* 
17.42 XIO* 
20.32 X 10* 
23.22X10* 
26.13X10* 


0.0i3445 
0.0<6890 
0.0ilQ34 
0.0sl378 

0.0il722 
0.0i2067 
0.0)2412 
0.00756 
0.0t3100 



Nan, 1 cram-cflJorie per sq. em. - 3.687 B.t.u. per sq. ft. 

1 gram-ealorie per sq. em. per cm. « 1.461 B.t.u. per sq. ft. per in. 

2 fram-calorie per see. per sq. cm. for a temp. grad. of 1 deg. C. per cm. 
^300 kilosram-caloriea per hour per so. m. for a temp. grad. of 1 deg. C. per m. 
«2.0O3 X 20* B.t.u. per hour per sq. ft. for a temp. grad. of 1 deg. F. per in. 



MATHEMATICAL FORMULAE 



TRZaONOMBTRIG FOBMULJE 

dn (—a?) « — sin x; ooa ( — x) = cos x; tan ( —x) =» — tan x. 



xfJ 




ton* X + oos' X » 1 ; tan x 



sin X 
cos X 



cot X B 



1 + tan* X « sec* x 
sin X ■» V 1 — cos* X  

cos X  V^l — sin' X — 



1 



cos* X 



tan X 
1 + cot* X = cosec* X = 



COS X 

sin x' 
1 



Bin*x* 



tan X 



1 



Vl + tan* X Vi + oot^ X* 
1 cot X 



Vl + tan* X Vl + cot* X* 



Fig. 1 



sin 2x * 2 sin X cos x; sin x » 2 sin Hx cos Hx; 
^ «06 2« ■• ooii* X — sin* x «» 1 — 2 sin* »  2 cos* x — I ; 

. _ cot* X — 1 

tan2x 



2 tan X 

- — ; cot 2x 



1 — tan* X 



2 cot X 



. « o . ^ . . . « 3 tan X — tan'x 

nn 8x — 3 sin X — 4 sin* x; tan 3x » — :-—;.- — i ; 

1—3 tan' X 

ooB 3x M 4 cos' X — 3 cos x; 

■in~^ X (read: anti-sine of x, or inverse sine of x; sometimes written arc 
sin x) means the principle angle whose sine is x. Similarly for cos^ x, tan~^ x, 
etc. (The principal angle means an angle between— 90® and +90** in case 
of sin"^ and tan'S and between 0® and 180® in the case of cos~^.) 

In the following the + or — sign is to be used according to the sign of 
the left-hand side of the equatiop. 

sin (nx) « n sin x cos*"* x — (n)t sin* x cos*"* x 

-f (n)j sin* X cos*"* x— . . .; 



cos (nx) =■ cos* X — (n)j sin* x cos*""* x -f- (n)4 sin* x cos*~* x — , 
where (ri)i, (n)s, are the binomi al coefficients. 

sin yix « ± VH(1 — OPS x); 1 — cos x = 2 sin* Hx; 

cos Hx = ± Vh(1 -h COS x); 1 + oos x ««= 2 cos* Hx; 

. .- — cos X sin X 1 — cos X 

tan Hx 



• 1 



4 



tan 



+ 46" 



•) 



'± 



-\- cos X 1 + cos X 
\l -si] 



sm X 



sm X 
sin X 



sin (x + y) » sin x oos y + cos x sin y; 

oos (x + y) » cos X cos y — sin x sin y; 

tan (x + y) «- [tan-x + tan y) -^ [1 — tan x tan y]; 

cot (x + y) = [cot X cot y — 1) -5- [cot x + cot yl; 

sin (x — y) =» sin x cos y — cos x sin y; 

cos (x — y) — oos X cos y -f sin x sin y; 

tan (x — y) « [tan x — tan yl -5- [1 + tan x tan yl; 

20 



MATHEMATICAL FORMULAS 21 

cot (af — y) — loot x cot v 4* 11 -^ {oot y — oot «!; 
eiaz+smys28in H(x + v) cos yi{z — y) ; 
nn J - sin y « 2 cos Hix + y) sin H(^ — V) \ 
cosz + Gos]/ =2 cos H(ae + y) cos >i(x — y) ; 
cos X — cos y = — 2 ain Mix -|- y) sin Hix — y); 

sin (jr + y) ^ , ^ sin (x 4- y) 

Un J + tan y « ^^ — -^ ; cot ar + cot y - --— — r-^; 

COS X cos y am X BUI y 

^ ^ sin (x — y) . sin (y — x) 

tan X — tan y — ^ ; cot x — cot y - . — : ; 

C06 X COS y sin X sin y 

an* X — sin* y * cos* y — ooii* x « sin (x H- y) sin (x — y) ; 
cos* X — sin' y •- cos* y — sin* x » cos (x + y) cos (x — y) ; 
an (45* + x) - cos (45° - x); tan (46° + x) « cot (45° - x); 
rin (45° - x) » cos (45° + x) ; tan (45° - x) = cot (45° + x). 

Eelatlong Between Three Angles off Plane Triuiglee 

il + B + C = 180°. 
' mn A + ain B + sin C - 4 coe HA coe HB cos HC; 

cos A + coe B +,coB C » 4 sin MA sin HB sin HC + 1 ; 

Bin A + sin B - sin C « 4 sin HA sin HB cos HC; 

cos A + cos B — cos C — 4 cos HA cos 'MB sin HC — 1; 

sin* A + ain« B + sin* C = 2 cos A cos B cos C + 2; 

sin* A + sin< B - sin* C » 2 sin A sin B cos C; 

tan A + tan B + tan C = tan A tan B tan C; 

cot HA + cot HB + cot HC » oot HA oot HB oot HC 

cot A oot B + cot A cot C -f cot B cot (7 = 1 ; 

rin 2A -h sin 2B + sin 2C « 4 sin A sin B dn C; 

sin 2A 4- sin 2B — sin 2C » 4 cos A cos B sin C. 

Selatlons Between Sides and Angles of Plane Triangles 

The parte of a plane triangle are its three sides, a, b, c, and its three angles 
X, B. C (A being opposite a, B opposite b, C opposite C, and A 4- B + (? >- 
180°). A triangle is, in general, determined by any three parts (not all 
angles). 

a : 5 : c :: Sin A : Sin B: Sin C. known as Law of Sines, 
e* * a* + b* — 2ab cos C, known as Law of Cosines. 

e coe B + & ooe C « a; tan H (A - B) « [(a - 6 -«- (o + 6)] cot H C. 

cos A « (6* + <5* - a«) + 26c or vers A « [a* - (6 - c)*l -f- 26c 

tan HB « r -f- (a — 6), tan HC ■» r - 4- (« - c), where a « H(o 4- 6 + c), 

and r * V(» - a){8 - 6) (a - c) -s-a. 

ain HA =» \/(« - 6)(a - c) +6c; cos HA. « Va(« - a) + 6c. 

Area — Hob sin C « Va(a - a){s - 6)(a - c) « ra, w h ere a - H( o 4- 6 4- c), 

and r « radius of inscribed circle « \/(a — o)(a — 6) (a — c) -^ t. 

Radius of circumscribed circle >■ B, where 

«.•> .. . .« .>-t -r>.'X.-®»^ <*6c 

2B»a-s-sinA a6-«-smB«c-f-8inC; r «4B sm 77 sin - sin - * --— • 

J 2 2 4/(a 

The length of the bisector of the angle C is 

2Va6a(a - c) ■y/ab{{a + 6J* - c*] 

** a4-6 " a 4- 6 " ' 

The median from C to the middle point of c is m « hV2(o* 4- 6*) - c«. 



22 MATHEMATICAL PORMULM 

ReUtlons Between Angles and Sidet of Spherical Triangles 

Let a, b, e be the sides of the spherical triangle, that is, portions of arcs of 
p'eat circles of the sphere; and let A, B, C be the angles of the triangle, that is, 
the angles made by tangents drawn to the sides at their points of intersection 
on the sphere. The sum of the angles will always be greater than two right 
angles, and may be nearly six right angles. The angle E'^A+B-^-C — 
180° is called the spherical excess of the triangle. 

sin a sin h sin h sin c sin c sin a 

sin A sin B* sin B sin C sin C sin A 

cos a "■ COB b COS c + sin h sin c cos A, 
with similar formulsB for cos h and cos c. 

cos A «= — cos B cos C -f sin B sin C cos a, 

with similar formulsB for cos B and cos C. 

In the spebial case of a right spherical triangle, in which C » 90°, 

. « cos A , cos B 

cos c = cos a COS b « cot A cot B\ cos a = ; — „ ; cos b « - — - ; 

sin B sin A 

, ^ sin a ^ tan 6 ^ . tan a . 

Bin A « -: ; cos A « : * tan A ** -: — r • 

Bin c tan c sm & 

The area of a spherical triangle _ spherical excess 

area of a great circle 180° 

DnrFBRBNTIAL TOBMULiB 

In the following formulse a, and n are constants, x, y and z are variables; 
e - 2.71828. 

1. <i a « 0. 2. d(o + a?) = dx. 3. d(ax) ■= orfz. 

4. d(x +y +2 + . . .) =dx +dy -^'dx+ . . . 

5. dixy) B xdy + ydx. For general case see 6. 



?-■■)■ 



(dx dy 
1- + 
x y 

7. dix^) » na^^^x. This formula is used in the case of reciprocals 

©dx 
« dx 1 ss — Ix"* dx » — — r-; 



dVx 


^dx^ 


« Haj- 


■«<fa- 




8. 


die') = 


e»dx. 






10. 


d Iog« X 


dx 

X 







9. dia*) « (log. a) a'dx, 

dx 
11. dlogiox= (logioc) — — 

X 

(0.4343. . .) 

X 

12. d sin X » cob xdx. 13. d cosec x ~ —cot x cosee xdx. 

14. d cos X « —sin xdx. 15. d sec x = tan x sec xdx. 

16. d tan x — sec' xdx. 17. d cot x »= —cosec* xdx. 

18. d sin"' X =« — • 19. d cosec * x « — 



Vl - X* xVx^* - 1 



MATHEMATICAL FORMULA 



23 



20. d coa~> ac « — 
22. d tan-i x 



^Ix 



At 



24. (f loK« sin z *> cot x<2x. 



26. d log« cos X s — tan xdx. 



21. d8ec"»x 



(ix 



23. d cot"» X « - 



25. d log. tan x 



xVi* - 1 
dx 

1 + X** 
2<ix 



sin 2x 



2dx 
27. d log, cot X -= — . — - 

sin 2x 



IKDIFINITK INTKQKAL8 

To integrate a function it is necessary to find a function which, when 
differentiated, will produce the given function. This may be done bj^ 
direct recognition, or by transforming the given function into a form where 
such recognition is possible. The following table gives the most common 
integrals; for a more extended list the reader is referred to B. O. Peirce's 
"Table of Integrals" (GinnA Co.). 

General FoRMVLiE 

1. J*adu - aj*du « ou + C 2. J^{u + v)dx «= J^wix + J*wiz 

3. fudv - Mf - fvdu 4. ff{x)dx « fnF{y)]F'{y)dy. x - F{y) 
5- y^'yy^Aa^.l/)^ = fdxJ*Kx.y)dy. 



6. Xxf'dx 



n -f 1 



Fundamental Integrals 
- H- C; when n has any value except — 1 



x 



7. y*^ - log,x + C = log, ex 8. y*c'dx = c' + C 



9, JfAd xdx ■» — cos X -h C 

« - oot X -h C 
dx 



1. r- 

•^ sin'x 



3- f'/ 

VI -X 

•^ 1 -f x« 



C08*X 

sin"* X + C  — cos"** X -{- c 



10. J cos xdx = sin x + C 
12. /* 



<2x 



« tan X + C 



« tan"' X + C' » — cot * x -f c 
Rational Functions 






(n + 1)6 



dx 



, . = - log, (a + 6x) H- C = — log, c{a + 6x) 
a -f- ox o b 






• -^ (o + 6x)» 6(a 4- 6x) "^ 



dx 



1 + X 



9. y- - Hlog, 

•^ 1 — X* 1 - X 



-f C * tanh-» X + C. 



when X < 1 



24 



MATHEMATICAL FORMULJB 



dx 



X - 1 



20. J*- = Hlog. — -— + C - - coth-i a: 4- C. when x > I 

X* — 1 X + I 



dx 1 



&** Vab 



— tan 



(>!•) 



+ C 



^^^'^ /~* 



log« — 7^ h c 



o - 6a?« 2Vab Vab - 6x 



Va6 



tanh-i 



m 



+ C 



when o > 0, 6 > 



23. f-—4- -. - ,J_ tan-i t±!^ + C \ ^^en 

^ o + 26x + cx« Vac - 6« Vac -6» /ac-&«>0; 



. y/h^ - ac — b -^ ex . _ 
log, - ,.. h C 



2\/b* - ac -y/b^ - oc H- 6 + ex 

es _ tanh 1 : + C. 

V fr' — oc V &* - ac 

24. ^ x" * (o + 6x)" (f X = - 



when 
6'- ac > 0; 



(m+n)6 



(m — l)a 



y x^-'Co + 6x)» <fx 



(m + n)6 



m 4- n 



m + n 



Irrational Functions 



25. J*Va + bxdx = lAVa + 6x)' + C 



36 



rfx 



. 26. y^ / =^ - - K V« -I- 6x 4- C 

V a + 6x ^ 

27. y \/a« + x« dx r= ^V^+ V» + I' log. (a: + Va« + xO H- C 

= -vo' + X* H- — sinh"* - + c 
2 2 a 

28. y Va* - x« dx « '\/a» - x« + ^ sin-^ * + C 

y 

29. y*\/x» - a^dx = -\/x« - a« - ^ log, (x + Vx« - aO + C 

= -\/x* — a» — - cosh** — }- c 
2 2 a 

Tranbcendbntal Functions 

30. Ca^dx^ r^^ + ^ 
•^ log. a 

«, /* , x»<!"r, n . n(n — 1) , «? 1 . ^ 

31. J3^^* dx = 1 -f ,, -. . . ± -r-A +C 

•^ a L ox o'x* a"x"J 

32. y log, xdx ^ X log* X — X + C 



MATHEMATICAL FORMULAS 



25 



^^^'^dx - -!^«if-i + c 



Oog, :r)' 



1 



33./ 

34. / 

35. y sin'xdx « - >4 sin 2ap + Hx + C « - H ainir cos* + Hx + C 

36. y coB« xdx «>i sin 2x+Hx + C-Hainxco8a;+ Ha: H-C 



da: « — -_ (loge «)*»+! + C 
n + 1 



37. ^/ sin mxdx *» — 



cos mx 



m 



+ C 38. J cos mxdx  



sin mx 
m 



+ C 



39. /tan asdlx « — log, coe a? + C 

41. y^ 



dx 



sin X 
<2z 



log.tan|+C 42. / ^"^ 



40. Jfsoi xdx « Iog« sin x + C 
log.tang + ^)+C 



t»n- + C 



44. 



cos X 
/* dx 



- cot - + C 



•^ 1 + cos X 2 ^ ^ 1 - cos X 

46, J*tair^xdx « xain'^x -f ^/l - x» + C 

46. /cos"* xdx « xcos~*x — V^l — x* + C* 

47. J^iAxr^xdx = xtan-» x - H log. (1 + x*) + C 

48. /oof xdx = X cof> X + >i log. (1 + x«) + C 

DXriNira INTSGRALS 

The definite integral of /(x)dx from x « a to x « 6, denoted by / /(x)dx, 
is the limit (as n increases indefinitely) of a sum of n term's: 

/V(«)dx = ^^|[°^ |/(xi)Ax +/(x,)Ax +/(x,)Ax + . . . + /(x„)AxJ, 

built up as follows: Divide the interval from a to & into r^m^fxV' 

n equal parts, and call each part Ax, ^ (b — a) -i- n\ in 

each of these intervals take a value of x (say xi, xt, . . . 

Xa), find the value of the function /(x) at each of these 

points, and multiply it by Ax, the width of the interval; 

then take the limit of the sum of the terms thus formed, 

when the number of terms increases indefinitely,' while YiQ, 2. 

each individual term approaches sero. 

Geometrically, / f(x)dx is the area bounded by the curve y = /(x), the 

X-axis, and the ordinates x » a and x » b (Fig. 2) ; that is, briefly, the "area 
under the curve, from a to &." The fundamental theorem for the evalua- 
tion of a definite integral is the following: 

that 18, the definite integral is equal to the difference between two values 
of any one of the indefinite integrals of the function in question. In .other 
words, the limit of a sum can be found whenever the function can be 
integrated. 
FroportlM of Definite IntegrftU. 

Theorem on Change of Variable. In evaluating /' /(x)dx, /(x)dx 
may be replaced by its value in terms of a new variable t and d<, and x ^ a 




26 



MATHEMATICAL FORMULJB 




Fio. 3 



and X ^h hy the corresponding values of ^ provided that throughout the 
interval the relation between x and / is a one-to-one correspondence (that is, 
to each value of x there corresponds one and only one value of /, and to each 
value of t there corresponds one and only one value of x). 

Approximate Methods of Integration. 
(1) Expand the function in a power series, 
and integrate term by term. 

(2). Use Simpson's rule or TchibyschefTs 
rule. 

(3). Use a planimeter. See p. 1414. 
Simpson's Bule. D|vide the given area. 
Fig. 3, into an even number of panels by 
'parallel ordinates drawn at constant distance 
h apart; denote the length of these ordinates 
by l/ot Vi. VSt • • • V»* Then to the sum of the 
end ordinates add four times the odd and twice the even, and multiply the 
sum thus obtained by one-third the common interval between ordinates to 
obtain the area; Area = HA[(vo + Vn) + 4(yi H- yi + j/s . . .) + 2 (ys 
+ t/4 + y< • • •)]• The greater the number of divisions the more accurate 
the result. 

The number of panels need not necessarily be even ; in a case where an odd 
number of panels is more advisable, to obtain the area add to the first ordinate 
four times the sum of the odd ones (except the last ordinate) and twice the 
sum of the last ordinate and of the even ones, and multiply the sum thus ob- 
tained by one-third the common interval between ordinates; in this case 
Area - HMl/o + 4 (yi + y* + Vs . • , •) + 2(y,» + y» + y4 .  .)]• 

Tchibyscheff'S &ule, based on similar assumptions to Simpson's Hule, 
employs fewer figures in its application and employs less ordinates to obtain 
a slightly more accurate result. The ordinates are not spaced equidistant, 
but in accordance with Table 1 ; having selected the numlx^r of ordinates to 
be used, this table gives the fractions of the half length of base at which they 
must l)e spaced, starting alwaysfrom the center line of figure, ' The ordinates 
are then measured off and summed, the sum thus obtained being divided 
by the number of ordinates. The mean ordinate thus obtained is multiplied 
by the length of base to obtain the area, thus: 



gum of ordinates 
No. of ordinates 



X Length of base » Area 



Table 1. TchibyscheS's Ordinate Table 



No. of 
ordinates 



Distance of ordinates from middle of base in fraotionB ot 

half the base length 





0.5773 


■« y 


10.7071 




0. 1876, 0.7947 




10.3745, 0.8325 
0.2666, 0.4225. 0.8662 






10.3239.0.5297.0.8839 




i 0.1679, 0.5288, 0.6010. 0.9116 
0.&38, 0.3127, 0.5000, 0.6873, 0.9162 


10 



MECHANICS OF RIGID BODIES 

BY 

M. W. TORBET 

Mechanies is the science of motion and force. 

Motion is CbAnge of Position. Change of position is a distance and 
can be represented by a length L. 

Telocity is Bate of Change of Position. When a change of position L 
takes place in a time T, the velocity is L -r T; example, miles per hour, feet 
per second, revolutions per minute. 

Acceleration is Bate of Chancre of Velocity. When a change of 
velocity Fs — Vi takes place in a time 7", the acceleration is 

(Fa — V\) -T- T orh -4- T*; example feet per second per second. 

Mass is Quantity of Matter. The mass of a body is the quantity of 
matter contained in the body. 

Weight is the attraction of the earth upon mass; it varies with 

latitude and height above sea level; example, pound, kilogram, weight is 

W 
mass X gravity, hence W — Mg and Af »= — 



Momentum is Quantity of Motion. The momentum of a body in 
motion is the mass of the body times its Telocity; hence MV = ML -s- T. 

Force is the Physical Quantity which Produces a Change in Mo- 
mentum. The change of momentum is equal to the force acting, hence 
force is mass times acceleration or F ^ M{Vt - Vi) + r » ML -^ T*. 

Work is force times the distance through which the force acts, 
beioe W ^ P XL = AfL* -^ T*; example foot-pounds, ergs. 

Energy is the Power to do Work. If a body gains or loses energy, work 
muit have been done upon it or by it. 

Kinetic energy is the energy possessed by a body in motion ; example, a 
falling body, a projectile. 

Potential energy is the energy possessed by a body at rest; example, a 
suspended weight, a compressed spring. 

Power is the Bate of Doing Work. If a certain amount of work W 
is done in a time J*, the power ia W -i- T ot ML* -5- T\ 

UNITS 

The Fundamental Units of Mechanics are Mass, Length and Time. 

The units of all other mechanical conceptions or quantities are derived from 
these fundamental units as shown in Table 1. All new formulsd should be 
ebecked to see that the dimensions of the result are consistent with the 
result desired. Dimensions used must belong to the same system, either 
foot-pound, second or centimeter, gram, second and "absolute" 
or "gravitational." 

27 



I 



28 



MECHANICS OF RIGID BODIES 



Table 1. Absolute Sjntems 



Names of quantitiea 



Dimensional 
formula 



Names of units 



Foot-pound-second 



Centimeter-gram- 
seeoi 



!r-gi 
>iid 



Length 

MasB 

Time 

Area 

Volume 

Moment oi area 

Moment of inertia (area) 
Velocity 



L 
M 

T 
L* 
L» 
L» 
L* 
L + T 



Momentum. 



Acceleration . 



Force 

Weight 

Moment of mass 

Moment of inertia (body) . 

Work 

Energy 

Power 



ML 



T* 



ML+ r« 
ML + T* 

ML 

ML* 

ML* -5- T* 

ML* -h T* 
ML* -h T* 



Foot 

Pound 

Second 

Square foot 

Cubic foot 

Ft.» 

Ft.< 

Feet per second 



Feet per second per 

second 
Poundal 
Poundal 
Pound-foot 

Foot poundal 
Foot poundal 
Foot poundals per 
second 



Centimeter 

Oram 

Second 

Square centimeter 

Cubic centimeter 

Cm.» 

Cm.< 

Centimeters per sec- 
ond 

"Bole" (proposed 
unit) 

Centimeters per I 
end per second 

Dyne. 

Dyne. 

Gram-centimeter 

Erg 
Erg 
Ergs per second 



In onflneerinf calculations generally, the uolt of force is taken as the weight 
of a pound and the fundamental units are length, force and tlxno. Their inter- 
relations are shown in Table 2. 



Table S. Kngineering or QraTltation Systems 



Names of quantities 



Dimensional 
formuln 



Names of units 



Foot-pound (foroc)- 
second 



Itength 

Force 

Time 

Area 

Volume 

Moment of area 

Moment of inertia (area) 

Velocity 

Acceleration 



Momentum . 
Work 



Energy . 
Power. . 



Weight 

Mass 

Moment of mass 

Moment of inertia (body) . 



L 

F 

T 

L* 

L* 

L* 

L* 
L ■¥ T 
L-h T* 

F X T 
FXL 

F XL 

rL+ T 

F 
FT* + L 
FT* 
FLT* 



Foot 
Pound 
Second 
Square foot 
Cubic foot 
Ft.» 
Ft.« 

Feet per second 
Feet per second per 
second 

Foot-pound (ft.-lb.) 

Foot-pound (ft.-lb.) 

Foot-pounds per sec- 
ond (ft.-lb. /sec.) 
Pound (lb.) 



Meter-kilogram- 
(force) second 



Meter 
Kilogram 
Second 
Square meter 
Cubic meter 
M.» 
M.« 

Meters per second 
.Meters per second 
per second 

Kilogram-meter 

(kg.-m.) 
Kilogram-meter 

(kg.-m.) 
Kilogram meters per 
second (kg. m./sec.) 
Kilogram (kg.) 



KINEMATICS 



29 



DlTlsions of Mechanics 

If only length and time are considered, mechanics is limited to the 
(•ometry of motion or kinematics; if only length and mass are con- 
ridered. it is limited to forces at rest or statics; while if mass, length and 
time are considered, it deals with bodies and forces in motion or kinetics. 



KINEMATICS 

Motion in a Straight Line — Rectilinear Motion 

Uniform Motion. If a point is moving in a straight line its position 

with refersDoe to a fixed point in that line may be d^ignated by a distance S, 

If equal distances da are described in equal times dt^ the velocity is said to be 

antfonn. The rate of change of position or Velocity of the point is v » d*/dt ; 

hence t « J^vdt. For uniform motion V »S + T,S '^V XT,T «5 + 7. 

Accelerated Motion. If the velocity of the moving point changes, the 
motion is said to be accelerated. The acceleration is the rate of change of 

the velocity, hence o = — — ti- 
ck w' 

If the velocity increases the acceleration is +• if it decreases, the accelera- 
tion is — . 

Uniformly Accelerated or Retarded Motion. If the velocity varies 
but the acceleration is constant, the motion is said to be uniformly 
wcelerated or retarded. The acceleration being constant, 

i«dt«/rf<» ir ^^ ^ai+v^8 '-So + Voi +Ha^*andH(r* -»••)- 
at 

«(#-#•). Or 

H the point starts from rest Vo ^ 0. 

Simple Harmonic Motion. If a point moves 
01 A circle with a constant velocity, its projection 
tpon a straight line in the plane of the circle 
^ a Simple Harmonic Motion. In Fig. 1 
the line Op revolves about O with a constant 
iDgnlar velocity w, q is the projection of p on the 
^ AB, and the motion of q is Simple Harmonic. 

VCOp is the angle ut, the distance « of q from 
Cm s sr sin tot; the velocity v » da/dt « wr cos 
«< ud the acceleration a » dv/dt = da/dt* « 
— •%• sin «if =» — «•«. 

The acceleration is always directed toward 0' 
>Bd is proportional to the distance a and the 
SQuie of the angular velocity m. When <at » 2t, 
^- - .etc., a, V and a have the same values, 




Fw. 1. 



^csce the period or time between equal values is t «> 2t/w. 
^^ Composition and Resolution of Velocities. Since a velocity has 
11 ^tvection and magnitude, it can be represented by a straight line; the direction 

iff the line representing the direction of the motion and its length the velocity. 

fceh a Une is called a vector. Two velocities may be combined by meanq 



30 



MECHANICS OF RIGID BODIES 



of the parAUelogrmm of motion as in Fig. 2, where V is the geometric sum 
or reittltont of the velocities t\ and vi. 

More than two velocities in the same plane may be combined by repeating 
the parallelogram and forming a polygon of forces, as in Fig. 3. 

In such a polygon the lines representing velocities should be drawn with the 
arrows following each other, the closing side with its direction raTened 
will then be the resultant. 

Velocities may be resolved into comiK>nents in the same plane in like manner. 
The velocity to be resolved into components is considered a resultant, and if 





Fxa. 2. 



Fio. 3. 



the directions of the components are known their magnitudes are obtained 
from the parallelogram. If the direction and magnitude of one component is 
known, the direction and magnitude of the other component are obtained 
from the parallelogram as before. 

Velocities in different planes may be combined or resolved by means of 
the purailelopiped of motion, Fig. 4, the resultant being the diagonal of 

the parallelopiped, and the components 
being the three sides meeting at o. 

Composition and Resolution of 
Accelerations. Accelerations, havinic 
magnitude and direction, can be rep- 
resented by vectors and combined and 
resolved by parallelograms and polygons 
in the same manner as velocities. 




Motion in a Curre- 
Motion 



-Curvilinear 



Fio. 4. 



If a point is moving in a curve its di- 
rection is tangent to the curved path and 
its linear velocity is v ■» ds/dt as in rectilinear motion. Since successive 
tangents are not in the same direction, tho acceleration is not in the same 
direction as the velocity. If at any point in the path the acceleration be 
resolved into components normal and tangent to the path and r and v be the 
radius of curvature of the path and the velocity tangent to the path at that 
point, then a» » v'/r and at — dv/dt. 



Van* + at* 



^(ty 



If the curved path be a circle of radius r, the linear velocity behig v and the 

s 



dill v~ 

angular velocity », then v ^ t^^ at •■ r ^r" and a» -» — 

dt r 



KINEMATICS 



31 



If equal circular paths are traveled in equal periods of time, v is constant 

and di^/dt =*o, ai=r— ««o and On = r*/r — 7«*. The angular velocity 

at 

w » 2r.V, ^ being revolutions per minute or per second as the case may be. 



Motion in a Plana 

While motion of a point in a plane n\ay take place in any manner the motion 
of a b6dy (plane figure) in a plane neoeeaitates that the distances between the 
particles of which it is composed do not vary, that is to say, the body must 
keep its shape during the motion. Such a body is a rigid body and its motion 
IS determined by two of its points. 

If a body moves so that every one of its points move in a straight line, its 
nMtion is called tranilation ; if every one of its points move in circles whose 
eeatrea lie in a straight line perpendicular to the planea of the eirdes, the 
motion is called rotation. 

The motion of any body in a 
plane can be reeolved into a 
translation and a rotation. In 
fig. 5, a body represented by 
two points A and B may be 
moved from the position AB to 
the position ii'B^ by a translation 
through a distance s and a rota- 
tion through an angle $, 

A body may be moved in a 





Fio. 5. 



Fig. 6. 



plane from any initial position to any other position by a single rotation 
about a certain point called the centre of the motion. In Fig. 6, the body 
represented by two points A and B may be moved from the position AB 
to the position A'B* by rotation about the centre O. 

When a body is subjected to a combined translation and rotation it may be 
eoaadered at any instant as rotating about the centre of the motion at that 
instant. Such a centre of motion is called an instantaneouii centre. 

far motion of a body in a plane the linear velocity and acceleration are the 

d*9 
■ame as for motion in a straight line, v -> da/dt and a » dv/dl « *r-j* and the 

angular velocity and acceleration are the same as for motion in a circle, 
• « d§/dt and a. - 4<«/d/ » d^0/dt*. 

The linear velocity at any instant is the angular velocity times the distance 
iram the instantaneous centre. 



32 



MECHANICS OP RIOID BODIES 



Motion in Spaoe 

In manner siinilar to Fig. 6 it may be shown that a body may be moved 
from one position to another in space by a single rotation and a single transla- 
tion. 

The axis about which, at any instant, rotation takes place, is called the 
instantaneous axis. 

STATICS 

By definition Forco is equal to mas9 times acceleration. If a particle has 
two equal and opposite accelerations its motion will not be changed. There- 
fore, the same effect follows if a particle is acted upon by two equal and oppo- 
site forces F ^ ma and F* ■> —ma; the combined effect of such forces is sero 
and the particle, if at rest, remains at rest, and if moving with constant 
velocity in a straight line will continue to do so. The subject of statics 
oonddera only foroat on bodies at rest. 

Bqullibrium. If the forces acting on a foody do not produce any accelera- 
tion, they neutralise each other, that is to say, forces which produce no accel- 
eration form a system in equilibrium. The body acted upon may be at 
rest or in motion, but if in motion the velocity must be constant. If 
a body tends to return to its original position after having been moved a small 
amount, it is said to be in stable equilibrium, if it tends to move further 
from its original i>06ition it is Baid to he in unstable equilibrium, and if it 
tends to -do neither, it is said to be in neutral equilibrium. 

Sztemal and Internal Forces. The force with which a body resists 
forces which tend to lengthen it is called tension. The force with which a 
body resists forces which tend to ahortefi it is called compression. The force 
with which a body resists forces which tend to slide one part of the body on 
the other part is called shear. 

Composition and Resolution of Forces. Since a force has direction 
and magnitude it may be represented by a line or vector in manner similar 
to a velocity or acceleration, and if two or more forces act on a single point 
of a body, their resultant single force may be found from a parallelogram or 
polygon of forces. A resultant may be resolved into components in the same 
manner as velocities or accelerations. For equilibrium the resultant must 
be zero. 

Couples and Moments. Two parallel, equal 
and opposite forces, + F and — F, form a couple, B 

whose moment is Fp, p being the perpendicular A 
distance between the 






forces, Fig. 7. Such a 

pair of forces tends to L _ ^ tF 

produce a rotation and 
cannot be reduced to a 
single force. A couple 
is not affected by rota- -F 
tion or translation in 
the same plane. Cou- 
ples in the same or Fi<j. 7. Fia. 8. 
parallel planes may be 

added algebraically. The direction or sense of a couple is -f* when it tenda 
to produce rotation in a right hai\d or clockwise direction and — if the 
reverse is true. 

Parallel Forces — Principle of Levers. The resultant of two or xnoro 
parallel forces is equal to the algebraic sum of the forces and act.8 througli. 
a point about which the sum of the moments of the forces is zero. In Fig. ^ 



STATICS 



33 



Ck the resultant of A and B if C « A +B and Aa ^ - B&, Aa + Bb ^ 0. 
This is known as the principle of levers and may be used to solve all problems 
in connection with them. 

O«noral Gonditioiis for Bquilibrium. For equilibrium of a rigid 
body the resultant of all the forces acting upon it must be zero and the 
sum of all the moments of those forces alK>ut any poiiU must also be sero. 
iX « 0, zr « 0, XZ « 0, 2Af = 0. 

Action of Couplet on Beams — Bending Moment — Torque. The appli- 
cation to a beam of forces forming a couple tends to distort the beam. If the 
couple acts in the same plane as the axis of the beam, it tends to produce 





Fig. 9. 



Fio. 10. 



bending, Fig. 9, and is known as bending moment, while if it aots in a 
plane perpendicular to the axis it produces a twist, Fig. 10, and is known as 
tvisting moment or torque. 



Centres of Gravity 

The action of gravity on a body produces a system of parallel forces acting 
OB the dements of mass of the body; the resultant of these forces passes 
through a iK>int such that the sum of the moments of the forces about that 
point is equal to zero. This point is known as the centre of gravity. The 
(distances of the centre of gravity of a body from codrdinate axes X, Y and Z 
•re represented by T, T and Z, and may be found by dividing the body into 
elements and adding the products of the elements and their respective dis- 
tances from the axis, then 



AG 

AG 
Ml 

It 



xifni 4" xtnit + xtm$. . ., whence x 



Xmx 



M 

yitnx + y*mj + ytmt. . ., whence 'y = — r^— and 

M 

, whence 2 = — r7~» or 



J^xdM _ y*y</A/ _ fzdU 
JdM JdM fdM 



M 



Straltflxl; Une. Centre of gravity is at the middle point of the line. 
3 



34 



MECHANICS OF RIGID BODIES 



Arc of Circle, Caa© l^Fig. 11, J - r mn c/c. y « 2r sin* H c/c; Case 2. 
Fig. 12, ar " r sin c/c, y = 0, 



X ^ -V t 

Y ^ 




Fro. 11. 



Fio. 12. 



Txiani^le. Centre of gravity is at intersection of lines joining middle 
points of the sides and vertices, Fig. 13. 





Fro. 13. 



Fig. 14. 



Parallelogram. Centre of gravity is at intersection of diagonals, Fig. 14. 

Trapeioid. Centre of gravity lies on the line joining middle points of the 

parallel sides and at distances y. ^ h(a + 2b) -5- 3(a + 6) and y^ * A(2a+&) 




Fio. 15. 

+ 3(a + 6) from the parallel sides a and 6. The position of the centre of 
gravity may be obtained graphically as in Fig. 16. 

Any Quadrilateral may be divided into triangles whose centres of gravity 
are known and the centre of gravity of the quadrilateral found by adding 



STATICS 



35 



the products of the areas of the triangles and the distances of their centre of 
gravity from the axis and dividing the sum of the products by the area of the 
figure. 

BegSMnt of drole. Fig. 16, 
' X ^ Hr sin* c + (c — ain c cos c). 

Sector of Cirele. Fig. 17, 

i « ?ir sin c -s- c, y * >ir sin'Mc. 

Any plane llgtiro may be divided into ele- 
ments perpendicular to the axis, adding the 
momenta of these elements about the axis and 
dividing the sum of the moments by the area 
of the figure, ^. 18. 

A modification of "Simpson's Rules" may 
be applied in finding the centres of gravity of 
figures bounded by smooth curves, such as 
the lines of a ship. Elquidistant ordinates are 
drawn and the end ordinate taken as the 
axis of moments. The ordinates are then multiplied by Simpson's multi- 




Fio. 16. 





Fig. 17. 



Fig. 18. 



ptiers and the products by the number of intervals from the axis as in the 
(ollowing table: 



iBterral or lever Ordinate 



SimiMon's 
multiplier 



Products for 
area 



Products for 
moment 






Vo 


1 


VI 




yi 




in 




y* 


y 


y» 


• 


Vn 



I 



\Xvo 
4Xyi 
2Xv* 
4X»i 
2Xy4 
4Xv» 
lXy« 




1X4Xyi 
2X2 Xyt 
3X4Xyi 
4X2Xy4 
5X4 Xy« 
6XlXy« 



Sum B> XA 



Sum - ZM 



Area - HA X 2il. moment *- Hh'ZM 
i - Hh*ZM + HhZA m hxM + 2A 

Extenaions of this method to computing centres of gravity of solids and 
eentree of buoyance will *be found in text-books and hand books on Naval 
Architecture. 

In tymmatrical lliruref or golids the centre of gravity lies on the axis of 
lymmetry. 

Prism or Cylinder with Parallel Bates. Centre of gravity lies midway 
between the bases on the line joining the centres of gravity of the bases. 



36 



MECHANICS OF RIGID BODIES 




Pyramid or Con*. Centre of gravilpr liee one-fourth the altitude above 

the base on the line jpiniug the vertex with the centre of gravity of the base. 

Determination of Centre of Gravity by Bzperiment. Suspend 

successively the body from two or more points and plumb down from each 

point of support. The centre of gravity lies at the intersection of the plumb 

lines. Place the body on 
knife edges on platform scales. 
Fig. 19, then the weight of 
the body is u'l -\- wt and tak- 
ing moments about one end, 
WtA " Wx and x - WtA/W. 

Moment of Inortia 

If in a rigid body the mass 
m of each particle be multi^ 
plied by the square of its 
FiG- 19. distance r from a given point, 

line, or plane, the sum of such 
products as mr* or Xmr* = miri' + rmri? -\- trw^ . . . computed for 
the entire body, is called the quadratic moment or moment of inertia, 
usually designated by /. If 2mr' « / « Afro*, the quantity r© is called 
the radius of inertia or radius of gyration. 

Plane figures may be taken as infinitely thin solids and area substituted 
for mass, hence / — Zar* = ^Iro*. The moment of inertia of a body com- 
posed of a number of parts about an axis is the sum of the moments of inertia 
of the several parts about that axis, / = /i -f /s + /» . . . 

Moments of Inertia about Parallel Axes. The moment of inertia of 
a body for any line or plane is the sum of the moment of inertia of the body 
for a parallel line or plane and the mass times the square of the distance be- 
tween the two lines or planes, / = /© + AfcP. 

Polar Moment of Inertia. The moment of inertia of a body about a 
point is called its polar moment of inertia about that point. The polar mo- 
ment of inertia is equal to the sum of the moments of inertia about any two 
axes at right angles to each other and intersecting at the pole. 

Moments of Inertia of Areas 



Rectangle about one side, Fig. 20. 

3 



7 « 



T 

I 

k 

I 

i_ 



-6 >J 




Fio. 20. 
Rectangle, about centre of gravity; Fig. 21. 

7 «_ >6W_l «_ 



Fig. 21. 



STATICS 



37 



Triaoisle, about base, Fig. 22. 

7 « — 
12 





Fig. 22. 
Triangle, about centre of gravity, Fig. 23. 

12 2 W 
Circle, about diameter. Fig. 24. 

^-64 "T- 



Fio. 23. 



36' 





Fig. 24. Fio. 25. 

Circle,- about centre (polar moment of inertia) Fig. 25. 

"* 32 2 * 

A modification of "Simpson's Rules" may be applied in finding the mo- 
ments of inertia of figures bounded by smooth curves; equidistant ordinates 
are taken and computations made as in the following tables. 

Moment of Inertia about Base 



No. of interval 


Ordinate 


Ordinate* -s- 3 


Multiplier 


Products 





V« 


HVf^ 


1 


I X Uv»» 


I 


VI 


\kfx* 




4 X Hvi* 




Vt 


^iyt« 




2 X Hy«> 




Vi 


Hv«« 


~ 


4 X Hv^ 




V* 


Jiyi' 




2XHl/«» 




Vk 


^iv** 


4 


4 X H!/»» 




y* 


Hv** 


I 


1 X Hv€> 



/ "• 2 products X }i interval. 



S products 



38 



MECHANICS OF RIGID BODIES 



Moment of Inertia about Ind OnUnata 



No. of 
Intonral 


Ordinate 


Multiplier 


Product 


Square of No. 
interval 


Products 


d 


yo 


1 


yo 








1 


V\ 




4»i 


1 


IX4yi 




ih 




Zvs 


4 


4X2itt 




Vt 




4y» 


9 


9X4ka 




y* 




ZV4 


16 


16 X 2V4 




Vt 




4y» 


25 


25X4yi 




V 


1 


y« 


36 


36X V« 



I ■• Z products X 



(Int.)« 



Z products. 



KINKTICS 
Newton'i Laws of Motion. I. Every body persists in its state of rest 
or of uniform motion in a straight line, unless it is compelled by external 
forces to change that state. II. Change of momentum is proportional to the 
external moving force and takes place along the line in which that force acts. 
III. To every action there is an equal and contrary reaction. 

Motion in a Straight Idne — Rectilinear Motion 
Uniform Motion. If a body is moving at constant velocity in a straight 

line, its momentum is MV » m — and its kinetic energy is HMV* » 



m 



(SY- 



di 



Accelerated Motion. If the velocity of the moving body changes, the 
change of momentum for unit time, is equal to the force acting upon the 

body, hence m— ■*»»,• ^ »«» ■* F, or if the force acts for a time t, Ft = 
di di* 

m{v\ — »o)- Since H(»i* — »o*) * o(«i — «o)f yifn{v\^ — i>o*) ■= ma{8\ — «o)i = 

F{9\ — «o)f or, the change in kinetic energy is equal to the force times the 

distance through which it acts, hence change in kinetic energy is equal to 

the work done. 

Simple Harmonic Motion. If as in Fig. 1, the distance of a body from 
a fixed point is « «■ r sin a»^ and its velocity v » otr cos tat, its momentum is 
mv B m<^ COB ut, and the force acting upon it is ma = — mtah- sin tU = 
— mM^s, that is to say, to produce harmonic motion the external force must 
be directed toward the centre and be proportional to the distance of the body 
from the Centre. 

Motion in a Circle— Rotation. The acceleration and therefore the 
force acting upon a body moving in a circle may be resolved into components 
tangent and normal to the circle. The component tangent to the circle is 

\nT -J-* or since mi* is the moment of inertia about the centre, P(r ^ I -t\ and 
dP dt^ 



de 
if the angular velocity -7 "" »* then Ptr 

dt 



diit 
mv* 



The force normal to the circle is F» » — and is called the centripetal 

T 

force. The equal and opposite force acting upon the axis is called the 
centrifugal force. 

Since the tangential force Ft acts at a distance from the centre equal to 
the radius r it is equivalent to a couple or Torque. H » F^r, therefore H * 

d<a 

I-r or the torque is equal to the moment of inertia times the angulai 
di 

acceleration. 



SECTION 2 

NON-FERROUS AND FERROUS MBTALS 

AND 
HEAT 

BY 

OTJILLIAM HBNBT ClaAMSB, B. S., First Vice-President and Secretaiy, 
The Ajax Metal Company, Pree. Ajn, Inst, of Metals, Mem. Brit. 
Inst, of Metals, A.8.T.Mm Am. Chem. Soc, Brit. Iron and Steel 
Jnet., Etc. 

D. J. MeADAM, XB.. M. S., Ph. D.; Metallurgist, U. S. Naval Experiment 
Station, Annapolis, Md., Mem. A.S.N.E. 

JOHN H. DEPPNLIB, M. E., Chief Engineer Thermit Dept. and Supt. of 
Thermit Plants, Metal and Thermit Corp., Mem. A.S.M.E. 

STUART PLinCLBT, Engineer-in-Chief, Engineering and Research Depart- 
ment, Davis-Bournonville Co. 

O. A. QOODSNOUOH, M. E.. Professor of Thermodynamics, University 
of Illinois. 



CONTENTS 



VON-FSBBOU8 lOTALg AlTD 
ALLOTS 

By G. H. CT.AMER 

Paox 

Pun Metals 41 

Brooies 53 

Brasses 66 

Strength of Metals and Alloys at 
Hiih Temperatures 68 

Bearing Metals 68 

White MeUl Alloys 78 

ISON AHD STIBL 

Bt D. J. McADAM, JIl. 



Ores of Iron 

Extraction of Iron from Ore 

Blast Fumaije Products 

Metallography 

Chemistry of the Purification Pro- 



Wrought Iron 

Bteel 

Ingots 

Mechanical Treatment. 
Heat Treatment 



79 
80 
81 
82 

87 
88 
89 
97 
98 
98 



Paos 

Influenee of Chemical Composition 

on Physical Properties 103 

Case Carburisation or Partial 

Cementation 109 

Cast Iron HI 

Ferro Alloys 119 

Specifioations for Wrought Iron .... 121 

Specifications for Steel 122 

Specifications for Cast Iron 148 

Protective Coatings for Iron and 

Steel • 163 

SOKIW THmiADB. BOLTS AND 
NVTS 

Screw Threads 168 

Bolts and Nute 161 

OXT-AOITTLBNS WKLDINO 

Bt STUART PLUMLEY 

Gases for Welding and Cutting 163 

Burners 164 

Expansion and Contraction 165 

Welding Rods 166 

Fluxes 167 

Welding 168 

Cutting 171 



39 



CX)N TENTS 



TBI TBUIMZT WU.DZNO PBOOI88 

By JOHN H. DEPPELER 

Paqb 

CompoRition 172 

Kindfl of Thermit 172 

Physical Properties 173 

Large Welds 173 

Crank Shaft Repairs 175 

Pipe Welds 176 



Bt g. a. goodenough, m: e. 

Professor of Thermodynamics, 
University of Illinois 

Temperature Measurement 177 

Expansion 178 

Specific Heat 180 

Freesing Mixtures 183 

Melting PoinU of Solids 183 



Paob 

Freeiing and Boiling Points 185 

Heat of Fusion and Latent Heat . . . 185 

Transmission of Heat 186 

Thermal Conductivities 180 

Thermodynamics 195 

Perfect Gases 200 

QfLB Mixtures 201 

Expansion of Gases , 202 

Ideal Cycles with Perfect Gases .... 204 

Air Compression 206 

Vapors, Properties of 208 

Steam Tables 200 

Refrigerants. 218 

Expansion of Vapors '223 

Mixture of Gases and Vapor 223 

The Steam Engine 226 

Refrigeration 227 

Flow of Gases and Vapors 231 

Throttling 237 



40 



NON-FERROUS METALS AND ALLOYS 

BT 
GUILLIAM HENRY CLAICER 



RKTEBmcis: Robert»>Aii8ten. ^' Introduction to the Study of Metalli 



luxgy, 
Fblton. " Prindplefl of Metalluivy/' MeGraw-HilL Hoffman. ** GenenJ MetaDur 
IT. " Alloys anoThflir Industrial ADplicatioii8t*' Lippinoott. 
M«Ul]ie AUoyi/* lippinoott. Brannt, " The MetaUio AUoys." Baiid db Co. 



MeGran^HilL Law. 



Lippinoott. 

or." 

Gulliver. 









Metal 


^a 


Atomic 
weight 


Specafio 
gravity 


Speci6o 
heat 


Melting 

point, 

deg. 

fahr. 


10,000 X 
coefficient 

of linear 
expansion 

per deg. 
fahr. 


Eleotrioal 

oonduo- 

tivity 


Aliimmwm 

Antimony 

Aneaie 


AL... 
Sb.... 

Ba... 
Bi. . . . 
Cd. . . 
Ca.. . . 
Ca... 
Ce... 
Cr... . 
Co. . . 
Cb... 
Cu. . . 
Ga... 

GI 

Au. .. 
In. . • . 
Ir. ... 
f e.. . . 
La... . 
Pb... 
Li.... 
Mg. . 
Mn.. 
£L|... 
Mo... 
Ni.. . . 
Os.. . . 
Pd... 
Pt.... 

Iv. ... 

Rh... 
Rb... 
Ru... 
Ag. .. 
Na... 
Sr. . . . 
Ta... 
To... 
Tl.... 
Th... 
Sn.. . . 
Ti.... 
vv. ... 

U.... 
V 

Yt... 
Zn... 
Zr 


27.1 

12D.2 

75.0 

137.4 

206.0 

112.4 

132.8 

40.1 

140.2 

52.1 

59.0 

93.5 

63.6 

69.9 

9.1 

197.2 

114.8 

193.1 

55.8 

139.0 

207.1 

6.9 

24.3 

54.9 

200.6 

96.0 

587 

190.9 

106.7 

195.2 

39.1 

102.9 

85.5 

101.7 

107.9 

23.0 

67.6 

181.5 

127.5 

204.O 

232.4 

119.0 

48.1 

184.0 

238.5 

51.0 

89.0 

65.4 

90.6 


2.56 
6.71 
5.67 
3.78 
9.80 
8.60 
1.87 
1.57 
6.68 
6.50 
8.50 

12.70 
8.93 
5.90 
1.93 

19.32 
7.42 

22.42 
7.86 
6.20 

11.37. 
0.54 
1.74 
8.00 

13.59 
8.60 
8.80 

22.48 

11.50 

21.50 
0.86 

12.10 
1.53 

1226 

10.53 
0.97 
2.54 

10.80 
6.25 

11.85 

11.10 
7.29 
3.54 

19.10 

18.70 
5.50 
3.80.. 


0.218 
051 
0.081 
0.047 
0.031 
0.056 
0048 
0.170 
0.045 
0.120 
0.103 
0.071 
0.093 
0.079 
0.621 
0.031 
0.057 
0.033 
0.110 
0045 
0.031 
0.941 
0.250 
0.120 
0.032 
0.072 
0.106 
0.031 
0.059 
0.032 
0.170 
0.058 
0.077 
0061 
0.056 
0.290 


1216 

1166 

1472 

1562 

518 

610 

79 

1481 

1152 

2741 

2714 


0.1280 
0.0563 
0.0306 


60.5 
4.4 


Barinm 




Kanuth 

Cadmium 

Cadnm 


0.0740 
0.1700 


12.0 
15.6 


Gtkium 






Cerium 












Cobalt 


0.0684 




Colofflbium 




Gtubum..* 


1981 
86 


0.0928 


100.0 


Ghdnum 






Gold 


1945 

311 

4172 

2768 

1490 

621 

367 

1204 

2237 

-38 

4532 

2642 

4530 

2822 

3191 

144 

3452 

100 

3270 

1762 

207 

1472 

5252 

825 

578 


•0.0800 
0.2320 
0.0389 
0.0672 


71 8 


Indittm 




Iridium 




Iron 


17.4 


laBthaaum 




Ud 


0.1624 


7 8 


litluum 




Jbcoealum 

■■mtnnoo 


0.1495 


35.8 


Ifolybaenum. . . 


0.3390 


1.7 


ffickd 

Olumum 


0.0706 
0.0361 
0.0651 
0.0495 
0.4680 
0.0472 


12.6 


Pklladtam 

Plaliiium 

Fotaanum 


15.4 
14.2 


Rhodium 




{tOadinm 




Mthcnium 


6 6534* 

0.1067 

0.3950 




film 

lodiam 


106.2 


Iliontium 




lutalum 


0.036 
0.049 
0.033 
0.028 
0.055 
0.130 
0.034 
0.028 
0.125 


00439 
0.0929 
0.1680 




nIariuA 




Haliium. ...... 

aorium 






{ftjuhim 


450 
3362 
5432 
4352 
3182 


0.1240 


12.0 








{UBuiiqn 






{Wadium 






Rferioa 








7.15 
4.15 


0.094 
0.066 


786 
2700 


0.1620 


27 2 


SKouinni ...... 











By the courteey of Mr. Lionel 
taaed from a aimilar aeetion 
Baadbook. MoGnw-Hill Book 



S. Marks muoh material for this section has been ob- 
by the same Author in the Mechanical Engineers' 



Co. 



41 



42 NON'FBRROUS METALS AND ALLOTS 

NON-FI&ROnS MBTAL8 
Gopper 

Copper is diBtinguished from all other metals by a peculiar red color, 
which is pinkish or yellowish on the fresh fracture of the pure metal, but in- 
clines to purple in the case of copper containing cuprous oxide. The fracture 
of cast copper is hackly granular; in forged or rolled copper it is fibrous and 
shows a pale red silky luster. Copper crystallises in the cubic system. 
Spceillo gravity': Pure crsrstalline copper, 8.940; electrodeposited copper, 
8.914; cast copper, 8.921; rolled and hammered copper, 8.952. Ordinary 
commercial copper is more or less porous, and its spedfic gravity varies be- 
tween 8.2 and 8.5. 

Copper is malleable and ductile. It becomes hard by rolling and draw- 
ing, but is readily annealed. It is completely softened by being held at a 
temperature of 350 deg. fahr. for 72 hr., or almost instantly when raised 
to a temperature of 600 deg. fahr. 

Mechanical Properties: S - 15,000,000 (about) ; tensile strength, lb. per 
sq. in., hammered, 38,400; drawn, 44,800; fire-box (rolled and annealed), 
32,700; special stay-bolt (annealed), 38,400. Elongation, 35-38 per cent ; 
reduction of area, 45-50 per cent. Shrinkage of castings, 0.1875 in. per ft. 
Compressive strength (cast), 40,000 lb. per sq. in. 

There are three standard grades of copper on the market, namely, 
Lake, Electrolytic and Casting. 

Lake Copper is obtained from the ores in the region principally bordering 
on Lake Michigan by wet concentrating methods. The concentrates are 
then smelted, az^d, after rabbling and poling, are cast directly into the form 
of copper ingots or bars. It is usually sold at a slight advance over electro- 
lytic copper. 

Klectrolytic Copper is produced in great part from the Western United 
States sulphide ores, which are first matted and then blown in a Bessemer 
converter to eliminate most of the iron and sulphur; the metal is then cast 
into slabs, known as "blister" copper, which usually carry about 96 per cent 
of copper. The blister copper is melted in large reverberatory furnaces and 
cast into anodes; these are dissolved in an electrolytic bath and deposited on 
cathodes, which are melted in reverberatory furnaces; after refining to 
eliminate impurities taken up in melting, it is oast into wire bars, cakes, slabs, 
ingots and billets. 

Casting Copper is obtained from ores which do not carry sufficient gold 
and silver to warrant the expense of electrolytic refining, and also from brass 
foundry by-products known to the trade as "copper-bc»aring material." It 
is produced by smelting and oxidising the ore or by-products in reverberatory 
furnaces until the impurities have been largely eliminated. Casting copper 
may range from 99 to 99H per cen*^ pure, depending on the raw material 
used and the degree of refining. It is considered inferior to electrolytic and 
lake copper, and sells at a slightly lower figure than electrolytic copper. 
Secondary casting copper, or that recovered from scrap copper, alloys 
and copper-bearing residues which occur as by-products in brass foundries 
and manufacturing plants where copper and copper alloys are used, runs 
from 98H to 99H per cent pure, depending on the raw material and the 
degree of refining. 

A. 8. T. M, Bpeciflcations (adopted, Itil) for Copper Wire Bars, Cakes, Slabs, 
Billets, Ingots, and Ingot Bars (Abstraet) : 

Mbta^ CoMTmm: The copper in all shapes to have a purity of at least 99.88 pe| 



COPPER 



43 



eeat, M determined by electrolytio assay, ailver being oounted as copper. (In the caae of 
faifk-resistaDce Lake copper, silver and arsenic are counted as copper.) 

RnsTiviTy. Low-resistance Lake copper iirire bars (ingots and ingot bars) to have 
areoBtivity not to exceed 0.1553 (0.15604) international ohm per meter-gram at 20 deg. 
(Odeg.) cent, annealed. Electrolytic copper in wire bars (ingots and ingot bars) to have 
a rcostivity not to exceed 0.15535 (0.15694) international ohm per meter-gram at 20 
dig. eent. annealed. High-reaistance Lake copper has a resistivity greater than 0:15604 
iatCToational ohm per meter-gram at 20 deg. cent. ' 

Wire, bars, cakee, slabs and billets to be ^ubetantially free from shrink holes, cold setd, 
piti; sloppy edges, ooncare tops and similar defects In set or casting. Five per cent 
vmriation in weight or M in. Tariation in any dimension from refiner's published list or 
pttrchaser's speeifieations may be considered good delivery. 

U. 8. ITafy 8p*cifle»tloni (Adopted, 191T) for Inf ot Copper (Abitraet) : There 
tre two grades, the percentage chemical requirements of which are as follows: Grade 
Ho. 1, copper 99.9 (min.), bismuth and antimony, none; Arsenic and sulphur, each 
0.0025 (max.)* Only high grade lake oopper or electro-copper, from ore of the best 
quality, will be accepted under this grade. Chrade Mo. t, copper, 90.75 (min.) ; bismuth, 
antimony, and sulphur, each 0.01 (max.); Arsenic, 0.03 (max.). Copper of this grade 
may be refined from the ore or reclaimed from scrap. Copper contents are determined 
by electrolytic aasay, ailver being counted as copper. 

Marine Uie. — Grade No. 1 is used in the manufaoture of high grade bronses and 
hraaaes; grade No. 2 for ordinary foundry purposes in compositions of commercial 
bnuB, east naval brass, screw pipe fittings, and commercial rolled brass, and gun metal; 
phosphor bronze; and other compositions not requiring great strength. , 

U. 8. Havy Speetteatloiis (Adofyted, 1918) for Sheet Copper for Bheathlng 
Wooden Craft require metal content of 99.5 per cent, pure copper. Sheets are fur- 
aiahed in standard aises 14 in. by 48 in., hard or soft rolled. 

A. 8. T. M. Spectfleatioag (Adopted, 1911) for Hard-drawn Copper Wire 

(Abstract): Wire to be free from all surface imperfections not consistent with the 
best commercial practice. Necessary brases to show at least 95 per cent of the tensile 
atrength of unbrased wire. Specific gravity assumed as 8.89. 

9ise to be expressed as the diameter of the wire in decimal parts of an inch (to three 
places). Permissible sise variations: For wire 0.100 in. in diam. and larger, ±1 per 
«eBt: for wire less than 0.100 in. in diam., 1 mil (-0.001 in.).. Coils to be gaged at 
both ends and near the middle. If, two points being within limits, the third is off more 
Ibsn 2 per cent (for wire 0.064 and larger) or 3 per cent (for wire smaller than 0.064), 
eoO may be rejected. 

Wire to have a tensile strength and elongation at least equal to the values given in the 
following table, aa determined on fair samples. 

Tabu %. Spodflcatioiui for Kard-drawn Copper Wlr* 



Diam., 
in. 


TonsUe 

strength, 

lb. per 

aq. in. 


Elon- 
gation 
in 10 in., 
per cent. 


Diam., 
in. 


Tensile 

strength, 

lb. per 

sq. in. 


Elon- 
gation 
in 60 in., 
j>ercent. 


Diam.. 
in. 


Tensile 

strength, 

lb. per 

■q. in. 


Elon- 
gation 
in 60 in., 
percent. 


0460 
410 
0.365 
0.325 
0.209 
0250 
0229 


49.000 
51,000 
52,800 
54,500 
56.100 
57.600 
59,000 


3.75 
3.25 
2.80 
2.40 
2.17 
1.96 
1.79 
in 00 in. 
1.24 
1.18 


0.165 
0.162 
0.144 
0.134 
0.128 
0.114 
0.104 
0.102 
0.092 
0.091 


62.000 
62.100 
63,000 
63,400 
63,700 
^,300 
64,800 
64.900 
65.400 
65,400 


1.140 
1.090 
1.176 
1.020 
1.000 
1.000 
0.970 
0.970 
0.950 
0.940 


0.081 
0.000 
0.072 
0.065 
0.064 
0.057 
0.051 
0.045 
0.040 


65,700 
65.700 
65,900 
66,200 
66.200 
66,400 

67.000 


0.92 
0.91 
0.90 
0.09 
0.87 
0.86 
0.85 


0204 


60.100 
61.200 




0.102 












Resisttvity to be determined by resistance measurements on fair samples at 68 deg. 
fshr.. and not to exceed 900.77 lb. per mile-ohm for wire from 0.460 to 0.325 in. in diam. 
or 910.14 lb. per mile-ohm lor wire from 0.324 to 0.040 in. in diam. 



44 NON-FEKROm METALU AND ALLOYS 

V. S. JlKTf BpMUBMloiu (AdopUd, Itll) for Hard-ftkwn Oopptr 
Bard-drawn flat Oopptr KatwUl faLlnw tbv above A. 9. T. M. Specific 
clonlr. No )>»«•■ BTc iilLciwed in the cue of fiat inBleiisl. 

CopIMT OutlDfl. Souod flipper cutiDRB in>y be mule in wnd or n 
by uldini about 1 per cent of boron soboiiilc Biu (conuuDiii« 0.08 to O.IO 
boron suboiicle) to tbe moUvn m«ta}. Tcosile alrrnath of flucb caetin^. 
per sq. in.: r[utic limit. 11.500 lb,; eloDsatian. 18.5 per cent; leductioD of 
per sent: electrical conduetivity, MhighuSTpei cent. 

v. 8. MaTT SiMciOcatletti (AdapUd, HIT) f«r KolUd CopiMr &i 
ShapM. and PUtw (Abitraet) : Minimuni pure copper oontenU. 69.5 per c< 
ieal requirementa For rods, bua, and ahapev; teoailo itrencth, lb- per iq. in. 
in 2 in., min.). gotl, 30.000 (25 per cent); hard, up to % in.. fiO.OOO (tO pe 
in, to I in..4S,000 (12 per oeat); 1 in. to 2 in., 40.000 <15 per cenll; 
3S.000 (20 per eeul). Physical rcquiremenU for aheeta and platea; teniii 
lb. per aq. in. (floncalion in 2 in., niin.), aolt, 30.000 to 40.000 (25 per o 
35,000 (IS per cent). Sheota IcB than 0.0T2 in. thick aeeti not be tested 

Hartna Um- Copper pipe, ahapea, reoeptac]e«, and aener 

VsiihH and Dimansloiii of Brasi and CoppsT Tabei are siven 
Weights and tbickneaBea of br*ti and copper thevti and bara a 
TabiM 3 to 6. For prapertiea of copper wire, see p. M. 



T»bl« S. W«l(bU ot Copp«r »nd Bnu BImsU and PlAtM 



« itrencth. 
ent): hanl, 
phyncally. 



B.A9. 


Lb. per 


>q.ft. 


a.ts. 


Lb. pai 


aq. ft. 


B. A a 


Lb. per sq. ft. 


155" 


Copper 


Bran 


■fif 


Copper 


Br^ 


^ 


Copper 


Bra.. 


oooo 


21 30 


20.40 


2 


.740 


.580 


jj 


657 


0629 


000 


]9'M 


1 .10 


3 


.330 






e:58i 


Otto 


oo 


1t,» 


1 .20 




.970 


:uo 


29 


521 


 499 





15.00 


1 .40 




.640 


.530 


30 


1.464 


0.444 


1 


11.40 


1 .80 


6 


.350 


.250 








1 


11.90 


1 .40 


7 


.100 


.000 


32 


a:»8 


0:3S2 




10 60 


1 .10 


S 


.m 


.790 


33 


0.328 


0)14 




9 46 












0.292 


0.279 




e.4i 


!a6 




'.4tt 


!420 




OliO 






1.50 


.18 


1 


.320 


.UO 


3« 


0.232 


0:211 








21 


1.170 


1.120 


37 


0.206 


0.197 










I.OSO 




3t 


O.IM 


0.170 




i'.T 


;o7 




0.»31 


o:e90 








1 


4.12 


4.5! 




0.8» 


OTO 


40 


0:i46 


OJIO 




4.20 


4.01 






0.706 








Thick- 






Thlck- 






'■fH^ 






ill. ' 






in.' 






"iT"' 








2W 


2.77 


» 


34. 


33;  




6t.t 


~~al— 




s.n 


5.S4 


hu 


37. 


36. 


u 








8.6a 


8.30 


!i 


40. 


38, 


19 • 








11.60. 


11.10 


i;ia 














14.50 


13.80 




46! 




IN * 








17.40 


16.60 


>U 




4?; 


81 :o 






S.30 


1V.40 




52: 


49.8 


I'Mi 


13.9 


at: 




13. 20 


22.ro 




55, 






86.8 


83 




26.00 


24.90 








I'ii* 


89.7 


«. 




2t.90 


27 70 




60:8 


5«: 




»2,6 


n^ 




31.80 


30 40 


H 


43.7 


60,9 

















Tabto 4. TUekBMiM ot Stuidud Copper ShaaU EoUad to Waif bt 



Lb. 


iTIiwk- 


rj., 


Thick- 


JA,. 


Thisk- 


Lb 


Thiok- 


Lb 


Thick- 


Lb 


Thlok- 




























in. 


iq. ft 


■n. 




in. 




in. 




in. 


«q. tt 










ona 










l?t 


0)71 




































i.im 






















































































10 


0.2lttt 





















( o;3*2 

0.241 
0.30I 
O 362 
O 422 
0.482 



I 450 
0.342 



I-090 
I.270 
(.450 






Stx'SXV^ o^ Sbeat Copper kt Varlouft Tamparktuxea 

(Id v*>f ""t ■>' tl" nrtngth at about + 30 del, fmlir.) 



^ Ha,TT BpadScatloni (Adopted ttlt) for (I) Phosphor Coppar, and li 

XUeon Copp"' reqotrw iKe (ollowing pfrwnlage cheniiral fonipositiuns: 

«^h« Copper: Ph«pho™. 10 (min): «,pp« 99,6 p-r «ot pur., 90 

Abod Coppw' Bilicon. 10 (min,); eopper, remalDder: iton, 0.6 (nmi.); BJuminui 



46 



NON-FERROUS METALS AXD ALLOYS 



0.1 (max.); tin and nnc, trao» (max.). The sam of copper, sUioon, umI iron ixmteiits 
shall not be leas than 99.8 pet cent; analysis shall be made from each heat or furnace 
charge. 

Marino Uae. For deoxidizing foundry alloys. 

Lead 

Sources. Practically all the lead on the market is obtained from the 
sulphide of lead ore, known as galena. Practically al! sulphide ores carry 
gold and silver, and crude lead is therefore subjected to further treatment 
for the extraction of the precious metals, and finally to an oxidizing refininK 
treatment which renders the lead extremely pure. 

Lead possesses a characteristic bluish-gray color and a dull metallic luster, 
which is lost on exposure to the air, the surface becoming dull gray. It is 
soft enough ta be indented with the nail and can be cut with a knife, the soft- 
ness of the metal increasing with its purity. It can be rolled into thin sheets, 
and, by previous heating, can be '* squirted" into rods and tubes; it cannot, 
however, be drawn into fine wire on account of its want of ductility and its 
low tensile strength. The specific gravity, between 11.254 and 11.395, is 
only very slightly increased by rolling (according to Knab, 11.352 for cast 
lead and 11.358 for rolled lead). The specific gravity is lowered by the pres- 
ence of other metals, so that it furnishes an indication of the softness and 
purity of the lead. 

Lead crystallizes in the cubical system. At a bright red heat, in the pres- 
ence of air, it volatilizes perceptibly, but only to a very slight extent if air 
be excluded; at a white heat (2900^560 deg. fahr.) it boils. Antimony, 
anenic, copper and zinc diminish the softness of lead when present to any 
considerable extent, antimony and arsenic rendering it brittle, hard and easily 
fusible. 

Mechanical Properties: E in lb. per sq. in. - 700,000 for rolled or cast 
lead ( ■» 1,000,000 for lead wire). Tensile strength in lb. per sq. in. » 1780 
for rolled or cast lead ( - 3130 for hard and 2420 for soft wire), ^hrinkage 
of castings, 0.3125 in. per ft. 

Table 7. Composition of American Pig Leads 

o — Southeast Missouri Undssilverised. d — Ordinary Common. 

6 — Southeast Missouri Desllverised. e — Ordinary Corroding — or Reined. 

0— Southwest Minouri Undeulverised. 

a 6 . c d 9 

Per cent Per cent Per cent Per cent Per cent 

Silver 0.0070 0.0004 0.0005 0.0005 0.0005 

Arsenic and sine trace trace trace trace trace 

Antimony 0.0030 0.0030 0.0020 0.0100 0.0050 

Bismuth 0.0030 0.0030 0.0030 0.0800 0.0500 

Copper 1 0.0600 0.0003 0.0190 0.0006 0.0006 

Iron 0.0015 0.0015 0.0016 0.0015 0.0015 

Cobalt and nickel 0. 0080 none 0. 0018 none none 

Lead -. 99.9175 99.9918 99.9722 99.9074 99.9424 

U. 8. Haty Specifications (Adopted, 1917) for Pigtiead require for No. 1 grade 
not less than 99.9 per cent of metallic lead to be the product of new ore only; Grade 
Ho. S, metallic'oontents not specified, may be either old or new lead. 

Marine Use, Grade No. 1 pig lead is used for foundry alloys and compoeitione; 
grade No. 2, for weights, ballasts, etc. 

PennsyWania B. B. Specifieatloni (Adopted, 190S) for Pig Lead specify that 
No. 1 grade shall contain not less than 99 ^i per cent of metallic lead, and No. 2 grade 
(used only for counterbalancing) not less than 97 V^ per cent. 



LSAD-ZINC 



47 



Chunical Lead. The lead sold in the United States under this name is 
obtained in the Flat River District in southeast Missouii, from disseminated 
ores which are contaminated with copper, cobalt, nickel and other impurities. 
Thb lead is alloyed naturally with certain percentages of other ingredi- 
ents which render it more imi>erviou8 to acid attacks than other brands of 
lead. The Hoyt Metal Co.» of St. Louis, manufacture a standardised 
eh^^Ir^f«Rl lead known as "Hoyt proceM" lead, which is furnished in the form 
of sheet and pipe. Hoyt metal is a lead canying from 6 to 10 per cent of 
antimony, and in the form of ^eets and pipes is extensively used in chemical 
vorks and other industries where acids are made or employed. The 10 pier 
cent Hoyt metal weighs 8 per cent less than chemical lead, its tensile strength 
ia double that of the latter, and it is much more rigid. It is claimed that it 
will not buckle, creep, stretch, tear or sag in use, and that it is much superior 
to chemical lead in acid-resisting qualities. 

Lead Pipe. For tables of sixes and weights of lead pipe and tubing, see 
pp. 1260 and 1261. 

Table 8. Maziinuin Sizes in WMch Sheet Lead Can Be Fximlshed 



Wcicht per aq. 


Max. 


aise in ft. 


Weight 

m . 


PJ*" Max. aiae in ft. 


ft., lb. 






aq 


. It.. 


lb 


• 




8X 20 






10 




11V6 X 40 


IVi 


8X 20. 






12 




11 X 40 or im X 35 




7 X 46 






14 




llVi X 40 orll^i X 30 


2H 


X 45 






16 




im X 40 orUH X30 




10 X 45 






20 




IIW X 40 or 1194 X38 


9H 


10 X 45 






20 




1194 X 36 




10 X 45 






24 




1194 X 30 




10 X 43 






24 




11 X 34 or IIH X 32 




10 X 43 or 


11 X40 




30 




11 X 27 otUH X 26H 




IIW X30 


or 1194 X25 




30 




im X 24H or 12 X16 




10 X 40or 


IIW X 36 




40 




11 X 24 or 12 X 16 


10 


llHXSOor 


11 X40or 10X48 




60 




12 X 12 



Zinc 

Zinc is a bluish-white metal having a ipeciflc gravity of about 7.1. It 
boils at about 930 deg. cent., so that it can be readily distilled; there is always 
a sensible loes when it is used in the manufacture of alloys. The metal in fine 
ihavings or vapor bums readily with an intense bluish-white flame, forming 
dense clouds of white sine oxide (philosophers' wool). It is malleable and 
ductile through a limited range of temperature only. It oxidizes only 
slightly on exposure to the air, with the formation of a basic carbonate. 

Zinc is marketed in the form of rolled iheets, and also in cast cakes of 

about 1 in. thick, known as fpelter. The cakes are very brittle, and break 

with a more or lees crystalline fracture. If the metal be nearly pure the crystal 

faces are large, bright and smooth; if there be a small quantity of iron present 

dull spots appear on the crystal faces; with an increased quantity of iron, as 

in dross spelter, the fracture becomes granular. The amount of iron present 

ean be fairly judged from the appearance of the fracture. Its tensile itrength 

11 low: 27,000 lb. per sq. in. along the grain; 36,000 across grain, for rolled 

sheets; spelter, 4000 (coarsely crystalline) to 14,000 (fine-grained). Modulus 

of rupture, 8000 to 22,000 lb. per sq. in., increasing with fineness of grain. 

Compressive strength (cast), 20,000 lb. per sq. in. E (average) 13,700,000; 

elongation, 12 to 38 per cent; reduction of area, 23 to 56 per cent. 

Zinc casts well, contracts but little on solidifying, and is largely used for 
tlie manufacture of statuettes and other ornamental castings which are usually 



48 NON-FERROUS METALS AND ALLOYS 

coated with bronse or brass by electrodeposition. Shriakage of oastings, 
0.3125 in. per ft. Its chief umb are in galvanizing and in the mannfactare 
of brass and other alloys. 

Zinc is never pure, the principal impurities being iron, lead, tin, copper, 
arsenic, and cadmium. When sine is used for galvanizing, a hard sine which 
contains several per cent, of iron accumulates in the vats. Good commercial 
spelter should not contain more than 0.05 per cent of iron, and this is about 
the maximum allowable for alloy making. 

Lead is invariably present in spelter in larger or smaller quantity. The 
other impurities are rarely present in objectionable quantities. 

Lead is invariably present in spelter in larger or smaller quantity. The 
other impurities are rarely present in objectionable quantities. 

Table 9. Typical Analyses of Various Orades of Virgin Spelter 

Iron Lead Cadmium Zinc 

Grade ' % % % % 

High grade 0.02(0.03) 0.05(0.07) (0.05) 99.930 

Intermediate 0.025(0.03) 0.15(0.20) (0.50) 99.825 

Brass special 0.025(0.04) 0.30-0.60(0.76) 0-0.50(0.75) balance 

Prime Western 0.08(0.08) 1.50(1.50) 0.50 97.920 

Sheet siPQt 0.015 0.27 0.29 99.400 

iMatthiessen & Hegelor Zinc Co. 

Hi|fh*grade spelter is used mainly for brass for spinning and drawing; for 
the highest grades of alloys, such as manganese bronze, and for galvanizing 
telegraph and telephone wires that have to withstand sharp bending; also 
for artistic castings. The intermediate grade is used in brasses and bronzes 
where the very highest quality is not essential, and also for the better grades 
of casting- brass. The brass special grade is used for the better grades of 
alloys where high ductility is hot required. Prime Western spelter is used 
mainly for the ordinary galvanizing of sheet, wire and miscellaneous articles, 
also in red-brass alloys and free-cutting yellow brass. 

Secondary Spelter is recovered by refining zinc dross — an iron-zinc alloy 
formed in the process of galvanizing. It carries from 3 to 5 per cent of iron 
and from 2 to 3 per cent .of lead. This is refined either by distillation or by a 
liquating method. If refined by the former method a product of fairly high 
purity results, and if refined by the latter method a very inferior quality re- 
sults, carrying a high percentage of iron and lead. This latter product is 
given a marketable appearance by the addition of a very small percentage 
of aluminum. 

A. 8. T. M. Specifications (Adopted, 1911) for Spelter. Limiting peroentagea 
of impurities are specified for the four grades of virgin spelter (see values in parentheses 
in Table 9), methods of sampling, analysing, etc. High, intermediate and brass apecial 
grades arc to be free from aluminum, and their combined contents of iron, lead and cad- 
mium are not to exceed 0.10, 0.5, and 1.20 per cent, respectively. 

IT. 8. Navy Specifications (Adopted, 1918) for Spelter designate three grades: 
(1) Grade A» virgin spelter, that is, spelter made from ore by a process of direct reduction 
and distillation, electrolysis, or a combination of the above; (2) Qrade B, high-grade 
spelter may include refined zinc, from short ends, etc., but not scrap metal; Orade G, 
which may include metal produced by refining by-products resulting from the manufac- 
ture of nonferrous alloys or similar metals. 

The Chemical Requirements of Grades A, B, and C, conform cloeely to the A. S. 
T. M. Specifications for High grade, Intermediate, and Brass Special, respectively. 



ZINC-TIN 



49 



«xeept thst U. 8w Navy Speeifioations require a mln. pure lino content of 00.85 per cent, 
90.35 per cent, and 08 per cent respectively. 

m 

M a rine Vwm. Grade A is euitable for the manufacture of manisaneae bronse, and 
other high-crade nonferroua alloyv; Grade B, for the manufacture of all other nonferroua 
aO<qrs; and Grade C, for galVaniiing purpoeos. 

Table 10. Weight of Sheet Zinc 

(Matthieasen db Hegeler Zinc Co.) 



Zine 


1 Thick- 
nea. in. 


Lb. per 
•q.fi. 


Zinc 


Thiok- 
neai, in. 


Lb. per 
sq.ft. 


Zine 


Thick- 
ness, in. 


Lb. per 
sq.ft. 




0.006 


0.22 




0.028 


1.05 


21 


0.080 


3.00 




0008 


0.30 




0.032 


1.20 


22 


0.090 


3.37 




0010 


0.37 




0.036 


1.35 


23 


0.100 


3.75 




0.012 


0.45 




0040 


1.50 


24 


0.125 


4.70 




014 


0.52 




0.045 


1.68 


25 


0.250 


9.40 




0.016 


0.60 




0.050 


1.87 


26 


0.375 


14.00 




0018 


0.67 




0.055 


2.06 


27 


0.500 


18.75 


10 


0.020 


0.75 




0.060 


2.25 


28 


1.000 


37.50 


II 


0.024 


0.90 


20 


0.070 


2.62 

















V: 1. Havy apoelOesUona (Adopted. If 17) for BoUed ZIno Pletee (Abstritet) : 
Metal content, not leas than 08.6 per oent pure sine, nor more than 0.08 per cent iron, 
aod must be thoroughly compressed by rolling to make a solid homogeneous slab with 
smooth surfaces free from all defects. The plates must be able to stand bending through 
of 4.5 deg. over a round surface whose diameter is 1 in. without breaks or crack 
St a temperature not exceeding 100 deg. fahr. 

Hull Zincs. Standard sise, 12 in. by 6 in. by H in. Other siscs for circular openinge 
sre given in the table below: 



Thirk- 
neas 


Standard Extreme 
sise sise 


Thick- 
; ness 


Standard 
sise 


Extreme 
sise 


Inch 

1/8 
1/4 
3/8 
1/2 


Inehn 
36 by 84 
36 by 84 
24 by 48 
24 by 48 


Inches 
60 by 96 
36 by 84 
24 by 72 
24 by 72 


Inch 

5/8 

3/4 

7/8 

1 


Inehe* 
24 by 48 
24 by 36 
24 by 36 
24 by 36 


Inehe* 
24 by 48 
24 by 48 
24 by 36 
24 by 36 



Zincs for Bollcn* Salfr-water Piping, etc. Standard sise, 12 in. by in. by H in> 
vith one central hole H in. in diam. Tolerance of 10 per cent over or under weight 
win be permitted, the weight of 1 cu. in. of rolled sheet sine being taken ss 0.2605 lb. 

Tin 

Sources. The principal tin ore is cassiterite, or tin stone — an oxide of 
tin. The lowest grades of pig tin come from China and Bolivia, and contain 
M little as 04 per oent metallic tin. Bancft tin has the highest reputation of 
any on the market, and next to this is Straits tin, from Malacca. Tin is now 
recovered from tin-plate clippings by an electrolytic or " detinning" process in 
the form of a fine powder, which is then smelted in a reverberatory furnace and 
cast into pigs. This by-product tin usually runs from 97 to 09 per cent of 
tin and carries lead, copper and antimony. For the production of the finest 
grades of solder. Babbitt metal and high-grade alloys subject to physical 
tests, Banca, Straits or similar grades of tin should be used. For all other 
uses the lower grades of tin are suitable, due consideration being given to 
their actual tin oonlent. 



50 



NON-FERROUS METALS AND ALLOYS 



Tin has an almost silvery whiteness with a slightly bluish tinge and a bril- 
liant luster which depends largely on the pouring temperature; if this is too 
high the surface -will show iridescent colors, while if too low the surface will 
be dull. The admixture of small quantities of lead, arsenic, antimony, iron, 
or bismuth also diminishes the luster of tin. 

The structure of tin is distinctly crystalline. Sp^eiAe grvritfi Cast tin, 
7.291; rolled tin, 7.299; electrically depod^d tin, from 7.143 to 7.178. 

MechAzilcal Propertiei. Tin is harder than lead but softer than gold. 
At ordinary temperatures it can be beaten and rolled into thin leaves (sheet 
tin and tinfoil). At higher temperatures its extensibility diminishes, 
untU at 392 deg. fahr. it iB so brittle that it breaks to pieces when hammered, 
and can be powdered. If the temperature at which tin is cast be either too 
high or too low, it will be "short," i.«., brittle. The addition of 1 to 2 per 
cent of copper or lead increases its hardness and tenacity. Tin is duoUla 
but possesses little tenacity (T.S. = 5000 to 5700 lb. per sq. in,; E ^ 5,700,000) ; 
it is most ductile at about 212 deg. fahr.; a wire 0.08 in. in diam. breaks 
under a load of 54 lb. For cast tin, tensile strength is 3500 lb. per sq. in. 
and compressive strength 6000 lb. per sq. in. 

Impurities and Their Effects. Iron, if present in considerable quantities, 
makes the tin hard and brittle; arsenic, antimony and bismuth, if present to 
the extent of 0.5 per- cent , reduce its tenacity; copper and lead (1 to 2 per 
cent ) make it harder and increase its strength, but make it less malleable; 
tungsten and molybdenum render it less easily fusible; stannous oxide 
reduces its tenacity: sulphur is said to render it "short." 



Table 11. Typical Percentage Analyses of Various Grades of Fig Tin 



Grade Tin 


Anti- 
mony 


Arse- 
nic 


Lead 


Bis- 
muth 


Cop^ 
per 


Iron 


SOyer 


Sul- 
phwr 


Banea 99,95 

Penang ,99.959 


0.007 
trace 
0.008 



to 
0.569 


'6,'6i3 
0.045 



to 
0.065 


trace 
trace 
0.034 
Oto 
4 00 
(China) 


■6!663 



to 
0.055 


0.018 
0.016 
0.052 
0.018 

to 
0.445 


0.045 
0.028 
0.003 

to 
0.028 




trace 


Singapore 

Range of impuri- 
ties in other 
grades. 


99.87 


0.006 
traces 


0.005 



to 
0.013 



U. S. Nary BpaciflcaUons (Adopted, 1917) for Ingot Tin require that the metal 
shall be free from scrap or rcmelted metal, in commercial and branded ingots of prime 
quality tin of the following percentage chemical composition: Pure tin, 99.76; with the 
following maximum impurities: Lead, antimony, arsenic, and copper, each 0.1; sulphur, 
0.01. The sum of all impurities shall not exceed 0.25. 

ICarine Use. Tin is used in making various bronse and bearing metal alloys, for 
coating condenser tubes, etc., and for making safety plugs for boilers. 

U. 8. NaT7 Specifications (Adopted, 1918) for Phosphor Tin call for the following 
percentage chemical composition: Phosphorus 3.5 (min.); impurities, 0.5 (max.); 
remainder, tin of at least 09.5 per cent purity. 

Ifarins TTss. For introducing phosphorus into foundry alloys. 

Antimony 

Sources. Antimony glance (known also as gray antimony ore, antimonite 
and stibnite) is the most important ore of antimony. It is a sulphide ore (con- 
taining 71.77 per cent of antimony in the pure state), and is commonly 
associated with quartz, calo-spar, heavy spar, and spathic iron ore* Zino 
blende and galena frequently occur intimately mixed with it. 



ANTIMONY-NICKEL 51 

Antimony is eharacteriied by its great briUiancy and by its color — silver 
white with a slight tinge of blue, the latter being increased by the presence of 
impttiitlM, such as sulphur, arsenic, lead, copper and iron. 

When pure molten antimony is allowed to solidify slowly and without dis- 
turbance under a layer of slag, a feni^like arrangement of raised lines radiating 
from the center appears on the surface of the metal (the so-called " antimony 
star"). This is generally regarded as an indication of the purity of the metal. 

FrodoctiOB. When the ores exist as pure sulphide of 90 per cent or over, 
they sze usually roasted direct to form an oxide, which is afterward reduced by 
esrbonaoeous matter. If the ores are lean the antimony sulphide is liquated 
to free it of the gangue, and then roasted and reduced in the same manner. 
By another method the antimony sulphide ia directly reduced by iron, which, 
having a greater affinity for sulphur than antimony, combines with the sul- 
phur and liberates the antimony. The antimony produced by both methods 
orast afterward be refined. 

A tjrpieal analysis of eommorcial aatimony shows the following percentage composi- 
turn: BOver, 0.001; arsenic. 0.120; tin, 0.006; lead, 0.089; copper, 0.076; iron, trace; 
■ae, none; niekel and cobalt, 0.046; manganese, none; sulphur, 0.008; antimony (by 
diff.). 0D.664. 

Harine Um. Antimony is used in making Babbitts and other bearing 
metak, its presence in alloys conferring the properties of hardness and of 
expanding on solidification. 

Nickel 

Nickel iKMsesses an almost silvery white lui^ter with a steel-gray tinge and 
great brilliancy. With groftt hardness and capacity for taking polish it 
combines great mftUeftbility; it can be easOy hammered, rolled, or drawn 
into wire. Sheets 0.0006 in. thick and wire 0.0004 in. in diameter may be 
made from it. Its tensile strength surpasses that of iron: for sheets of pure 
niekd 0.05 in. thick, rolled hard (annealed), 92.000 lb. (76.000 lb.) persq.in. 
and 11 (35) per cent elongation in 2 in.; for 0.065-in. diam. hard-drawn 
wire, 150,000 to 160,000 lb. per sq. in. 

Nickel is attracted by a magnet, and then becomes magnetic itself; it 
loses this property at 662 deg. fahr. It can not only be welded to itself at a 
white heat, but it can also be welded to iron and certain alloys. Fleitmann's 
method of manufacturing nickel-plated wares consists in welding pure nickel 
to iron and steel or alloys of copper and nickel, and then hammering or 
rolling into sheets. In welding, it is necessary to completely exclude the air 
from the surfaces to be welded. 

Commercial nickel is exceedingly impure, eontcdning substances of which 
eren traces affect its valuable properties. The most harmful impuritief are 
arsenic, sulphur, oxide of nickel and chlorine. Carbon is dissolved by molten 
nickel, and seems not to affect its good qualities so long as oxides are not pres- 
ent at the same time. It makes nickel slightly more fusible. According to 
Ledebur, nickel abeorbs its own monoxide, and this injures its tenacity and 
malleahUity. 

Nickel d06g not tarnish in dry air at ordinary temperatures. When 
heated in contact with air it is slightly oxidised into nickelo-nickelic oxide. 
At a red heat it decomposes steam very slightly. It is very little acted upon 
by hydrochloric or sulphiuic acid in the cold, but is readily dissolved by dilute 
nitric acid and aqua regia. 

Froduction. The chief ores of nickel are the silicate ores of New Cale- 
donia, known as garnierite, and magnetic pyrites containing nickel and copper 
found in Ontario. The silicate ores can be treated by direct reduction, al- 



62 NON-FSRROVS METALS AND ALLOYS 

though they are usually treated in oonneotion with sulphide ores. The mag- 
netic pyrite ores are first smelted to form matte. This matte is Bessemerised 
to oxidise the greater portion of the iron and sulphur, with the production of 
a nickel-oopper matte which is afterward fused with sodium sulphate and 
ooal, forming an easQy fusible matte with the copper sulphide which ifi of less 
specific gravity than the nickel sulphide, and a fairly complete separation can 
be made because of the difference in the specific gravity of the two mattes. 
By repeating the process, practically pure nickel sulphide is produced, which 
is then roasted to form oxide and finally reduced to metallic nickel. Mond's 
method consists in roasting the Canadian mattes, eliminating the copper by 
sulphuric add, and then exposing the resulting product to the reducing action 
of producer gas at about 660 deg. fahr. The reduced metal is then exposed to 
the action of CO at 176 deg. fahr. in a " volatiliser," the nickel, carbonyl so 
formed being received in a chamber heated to about 390 deg. fahr.. where it 
decomposes, the nickel being deposited and the CO returned to the volatiliser. 
Nickel as ordinarily reduced by carbon is brittle, but by the addition of a 
small percentage of magnesium or manganese, it can be made ductile. 

A tsrpioal percentage composition after the addition of magneBium is as follows: Nickel, 
98.24; cobalt, 1.09; iron, 0.36; copper, 0.10; silicon, 0.06; magnesium, 0.11. 

Marine Use. In nickel steels, plating, in the preparation of German 
silver and other alloys, resistance alloy wires, anodes, etc. 

Aluminum* 

Aluminum (aluminium) f is a white metal closely resembling tin in color, 
produced electrolytically in large quantities from alumina prepared from the 
mineral bauxite — a hydrated oxide of the metaJL Jts ppecific gravity at 
62 deg. fahr. ranges as follows: Pure aluminum, 2.56; pure aluminum sheets 
and wire unannealed, 2.68; pure aluminum sheets and wire annealed, 2.66; 
aluminum alloy sheets and wire unannealed or annealed (3 S), 2.7$;' alumi- 
num casting alloys, 2.82 to 2.99. The alloys contain small percentages of 
Cu, Ni, W, Mn, Cr, Ti, Zn or Sn to produce hardness, rigidity and strength. 

Ordinary commercial aluminum has about the hardneas of copper. By 
pressing, rolling, forging, stamping or other similar working it may be made 
very hard and rigid in the finished shapes, whereas the soft annealed metal 
would be too weak for the purpose intended. This is especially true of alu- 
minum alloyed with other metals in amounts not to exceed 5 or 6 per cent 
Greater percentages render aluminum base alloys non-malleable. 

Aluminum is very ductile. It can be rolled into sheets as thin as 0.0007 in. 
and then be beaten into leaf; drawn into wire as small as 0.004 in diameter; 
spun, stamped or extruded in various shapes. It is susceptible of a high 
degree of finish by ];>olishing or burnishing. It becomes hardened by work- 
ing, and sheets for stamping or spinning must be annealed. 

At ordinary temperatures aluminum is highly resistant to all inorganic 
aoidi except hydrochloric. Solutions of caustic alkalines, chlorine, bromine, 
iodine and hydrofluoric acid rapidly corrode the metal. A clean surface 
tarnishes in damp air, an almost invisible coating of oxide being formed, 
which, however, is very permanent and prevents further attack. 

As the common metals are electronegative to aluminum in a voltaic couple, 
care should be taken that aluminum exposed to water or aqueous solutions 
shall not come in contact with any other metal that will cause galvanic 

* Much of this information has been obtained from the publications of the Alumioum 
Ck>. of America, 
t Trade usage in North America sanotions the use of the word aluminum. 



ALUMINUM— BJIONZBS ^ 

iiStion to be set up. Eor example, tabing can be tlioioaghly kiMilaied by the 
nae of rubber gaskets, washers or nuts. Aiuminum sheets and shapes can 
be insulated from other metal by the liberal use of good heavy paint between 
the joints. 

Commercial aluminum is sold in three grades: No. 1 (pure), No. 2, and 
extra pure. No. 1 has approximately the following compoaition: Silioout 0.30 
per cent; iron, 0.15 per eent; aluminum, 99.65 per cent. For No. 2 the 
percentages are respectively 2, 2 and 96. Silicon and iron are the only 
impuritlog commonly found In aluminum. 

The teoiile and oompreisive ttrongths of aluminum (99 per cent pure) 
STsrage as follows: 

Tension 

Ultimate Reduction 
£U«tio limit, strength, of area, 

lb. per sq. in. lb. per sq. in. per cent 

Ctttinsi 8,500 12.000-14,000 15 

Sheet 12,500-25,000 24,000-40.000 20-30 

Wire 16,000-33.000 25.000-65.000 40-«0 

Ban 14.000-23.000 28.000-40,000 30-40 

Compreeeion 
Short east columns (heisht - 2 X diam.). 3,500 12.000 

E tor east aluminum « 9.000.000. 

Pure aluminum in castings is a metal somewhat open in texture, and when 
med for cylinders to stand pressure an increase in thickness over that calcu- 
lated by ordinary formulo should be made to allow for its poroiity. Shrink- 
age of castings, 0.2031 in. per ft. 

Under transverse tests the metal will bend nearly double before breaking. 
Jh& strength of aluminum is greatly improved by forging or pressing the ingots 
at a temperature of about 600 deg. f ahr. 

U. g. Xavy Speeiileations (Adopted, 1918) for Ingot Aluminum: Aluminum 
to be maaefactured from bauxite or other hich-grade ore, metal reclaimed from ttntp 
tM bdns acceptable. Percentage efaemieal requirements: Aluminum (min.). 99.4; 
iron and sSioon each (max.), 0.6; other impurities (max.), 0.1. The sum of iron, siUcon, 
and other impurities not to exceed 0.6. Ingots are to be of commercial standard form 
and shape, to be clean, free from adhering dirt, slag or foreign matter, and shall have 
nonnal and uniform shrinkages. 

Marine Use. Suitable for the manufacture of castings and ingots for forging pur- 
poses of aluminum, aluminum bronae, manganese bronse. etc 

Bstnided Aluminum can be obtained in shapes possible to manufacture 
no other way, and in any continuous lengths desired. It is possible to extrude 
shapes in compositions ranging from pure aluminum to very hard alloys^ some 
of which cannot be rolled. The tools used are much less expensive than are 
the rolls ne co s ear y for rolled shapes, making it commercially possible to fur^ 
aish smaller quantitiee of speeial shapes than rolling-mill costs would justify. 
The maarimiim sectional dimension of an extiMded shaped should not exceed 6 
in., and in general, walls under fj in. in thickness should not be specified. 

BRA88I8 AND BBONZI8 

Copper-Tin Alloyi (Bronses) 

The term iMrooJM should be applied only to those alloys of copper in which 
tin is the predominating metal affecting or modifsring the properties of the 
copper. A true bronse is an alloy of copiper and tin only, in which copper 
is in predominating proportion, the most useful alloys being those containing 
from 4 to 25 per cent of tin. Aiter 12 per cent of tin is exceeded, the ductility 



54 



NON-FERROUS MSTALS AND ALLOYS 



of the alloys ia ao diminiBhed that they are subject to breakase by ehoek. 
ModiiicatioDfl are often made by the addition of relatively small proportions of 
lead and sine, and occasionally of other metals. 

Table IS. Properties of Various Copper-Tin Alloys 

(From Report of U. S. Test Board. 187^1881) 



Compod- 

tion b^ 

analysiB 






i 



I 

o 

I 



h 

aa • 

.2 fi 
'ttO, 



9 






O u 



a 

V3 



o 



I? 
(Si 



r 

•I* 



i 



100.00 
97.89 
96.06 

90.27 

87.15 

«0.95 

76.64 
69.94 
68.S8 

65.34 
56.70 
44.52 
34.20 
23.35 

15.08 

11.49 

8.57 

3.72 

0.00 



0.00 
1.90 
3.76 

9.58 

12.73 

18.84 

23.24 
29.88 
31.26 
34.47 
43.17 
55.28 
65.80 
76.29 

84.62 
88.47 
91.39 
96.31 
100.00 



8.791 
8.564 
8.649 

8.669 

8.681 

8J4Q 

8.565 
8.932 
8.938 
8.947 
8.682 
8.312 
8.013 
7.835 

7.657 
7.552 
7.490 
7.360 
7.293 



Copper red... 

Red 

Reddish- 
yellow 

Urayish- 
yeuow 

Mottled 



Reddish^ 
gray 



White 

White 

Bluish'^pwy. 

Light grav.... 

Grayiab-wnito 

Graybh-white 

Grayish-white 

Qrayisk*white 
Grayioh-whito 
Grayiah-white 
Grayish-white 
Grayish-white 



Fibrous... 
Vesicular. . 
Vesieular.. 

Earthy.... 

finely 

▼emoular 
Ilaely 

granular 

Smooth. . . . 

Conehoidal 

Conchoidal 



Stony. 



Crystalline 
Finely crys- 

talUne 
Crystalline 
Crystalline 
Granular.. 
Granular. . 
Fibroxis... 



27800 
24580 
32000 

26860 



29430 
32980 



22010 22010 



5585 

1620 
2201 
1455 
3010 
3371 
6775 

6520 
63801 
6450 
4780 
3505 



14000 
10000 
16000 

15750 



20000 



5565 

•  • • • 

2201 
1455 
3010 
3371 
6775 



3500 

3500 
2750 



29848 

• • • • • 

33232 

49400 

3453] 

56715 

32210 
12076 
9152 
4776 
'2126 
4776 
5384 
12406 

9063 
10706 
5305 
6925 
3740 



6.47 
13.33 
14.29 

3.66 

3.33 

0.04 

0.00 
0.00 
0.00 
.00 
00 
00 
.00 



0. 
0. 
0. 
0. 



0.00 



4.10 

6.87 

12.32 

35.51 



bent 

  • a 

bent 
bent 
4.00 
0.49 



19 
.06 
.04 
.02 
.02 
03 
0.04 
0.27 



0. 
0. 
0. 
0. 
0. 




0.86 

5.85 

bent 

bent 

bent 



42000,143 
34000 150 



42048 
38000 
53000 

78000 

114000 
147000 



84700 



35800 

19600 



6500 
10100 
9800 
9800 
6400 



157 

175 

182 

190 

122 
16 



16 



23 

17 



23 
23 
23 
23 
12 



153.0 
317,0 
247.0 

II4.0 

100.0 

16.0 

3.4 
1.5 



1.0 



1.0 
2.0 



25.0 
62.0 

132.0 
220.0 
557.0 



Test pieces for compression tests were 2 in. long, H in. diam. 
Test pieces for tomon were 1 in. long. 9i in. diam. 

Qun Metal is a oopper^tin alloy (8 to 11 per cent of tin) used before the 
introduction of steel in the manufacture ordnance. Occasionally it contains 
small pereentaices of iron, sine and lead. 

V. S. Navy Bpeellleatlons (Adopted, 1010) for Oun Metal (Abstracts) : Per- 
centage chemical requirements: Capper, 88; tin, 10; rinc, 2. A variation of 1 per cent 
is allowed above or below. Iron not to exceed 0.06 per cent; lead not over 0.2 per oent. 

Mininmm physioalpropsrties: Tensile strength, 30,000 lb.; yield point, 16,000 
lb.; elongation in 2 in., 16 per cent* Thia alloy is susceptible to quite ¥^e variation 
in its physical properties, due to the temperature at which it is poured, the speed at 
which it ooolis, the subsequent heat treatment which it has had, the manner of attaching 
test bar, gating and provioon for shrinkage. It can also he modified by slight additions 
of deoxidizing agents. 

Marinie Use. All composition valves 4 in. in diameter and above; expansion jointa, 
flanged pipe fittings, gear wheels, bolts and nuts, miscellaneous oonitx)<>ition castings, all 
parta where strength is required of compnaition oastiugs or where subjected to salt water, 
and for all purposes where no other alloy is specified. 

Compoaition «aJ«««, safety and relief, feed check and stop, surface blow, drain, air, 
and water cocks, main stop, throttle, reducing, aea, safety, sluice, and manifolds at 
pumps. 



BRONZES 



55 



Heads, sliapes, and water chesto far eondensen, distillera, feed-water heaters, and 
oil coolers. 

Pump*. Air-purop casing, valve TCats, buckets, main circulating, water cylinders, 
valve boxes, water pistons, stuflSjug boxes, followers, glands, in general the water end 
of pumps complete except as specified. 

Stnfino box glandf and tnuhin^t. 

Blower bearing boxee. 

MUeeiianeoua. Grease extractors, steam strainers, separators, easing for stem tube 
and propeUer shafts, propeller hub caps. 

Searingtn Main, stern tube, strut, and spring. 

U. 8. Hftvy SpeeiAeatioiia (Adopt«d| lOiO) for Bronae Valfv OMtlact eall for 
the following percentage chemical composition; Copper (min.), 87; tin (min.), 7; sine, 
remainder; iron (max.), 0.06; lead, (max.), 1. Scrap will not be used, except such as 
may result from the manufacture of articles of similar composition. Color of the frao- 
|Ure section and grains of the metal must be uniform throughout. Castings must be 
^ound, clean, free from blowholes, porous places, cracks, or any other defects that ndte- 
fially affect their strength or appearance or which indicate ai» inferior quality of metal. 

Maiina Uaa. This material is suitable for valves below 4 in. for steam and general 
purposes for which the material is not otherwise specified, manifolds and cocks, relief 
valves, eomposition lug sockets, and pad eyes not requiring special strength; hose 
eouplings and fittings. 

U. 8. TtKwj 8p«eifleatloiu (Adopted, 1910) for Journal Bronse require the fol- 
lowing percentage chemical composition: Copper, 82 to 84; tin, 12.5 to 14.5; sine, 2.5 to 
4.5; iron (max.), 0.06; lead (max.), 1.0; normal proportions, 83-13.6-3.6. 

Karine Vso. This material is suitable for the following purposes: Bearings, jour- 
nal boxes, bushings, and sleeves, slides, slippers, guide gibs, wedges on water-tight doors, 
and all parts subject to considerable wear, for reciprocating engines in valve stem cross- 
bead bottom brass, link block gibs, and suspension link brassM. 

Table 13. Melting Points of Varioui AUoyo 

(From Technical Paper No. 60, U. S. Bureau of Mines) ' 



Alloy 


Coaaposition by 
analysis 


Melting 
point. 




Cu 


Zn 


8d 


Pb 


deg. fahr. 


nntt maital 


P.ct. 


P.ct. 


P.ct. 


P.ct. 


1825 


lyfNKifHi gun nwtal 


85.4 


1.9 


9.7 


3.0 


1795 


Red brass 


1780 


Low-crade red brass. ...................... 


81.5 


10.4 


3.1 


5.0 


1795 


Lfadfld bronse 


1735 


Brmae with smo ..tr-,--,-^, --7-', ■,■,,-, 


84.6 
75.0 
66.9 
61.7 


5.0 
20.0 
30.8 
36.9 


10.4 
2.0 

"i.V 


2.3 


1795 


Half yellow, half red 


1690 


Gast vdlow brass 


1645 


Maral hmss. , 


1570 


^''"^^KiMse bmnse. ..,-■.... 


1600 













COPPEB-XINC AULOTS 



COPFBB-TXN AlIiOTB 



ParUby weight 


Melting x>oint 


Parts by weight 


Melting point 


Copper 


Zino 


Deg. f ahr. 


Copper 


Tin 


Deg. fahr. 


95 
90 


5 
10 
15 
20 
25 
30 
35 
40 


I960 
1930 
1880 
1830 
1795 
1725 
1660 
1635 


95 
90 
85 
80 


5 
10 
15 
20 


1920 
1840 
1760 
1635 


85 

•0 


CoppEB-LEAD Allots 


15 
70 
65 
60 


Copper 


Lead 


Deg. fahr. 


95 
90 
85 


5 
10 
15 


1950 
1920 
1095 



66 NON-FERROUS METALS AND ALLOYS 

■ff«et of H«At TrsfttiiMBt. As these alloyi oontain different eonstituents wlileh are 
•table only at certain elevated temperatures, the effect of quenching alloys at those tem- 
peiatures at which the Taxious constituents are stable will result in the propertin of 
the alloys being modified by reasonof containing such constituents. This accounts for 
the fact that bronse acts in a manner reverse to steel when quenched above 990 deg. 
f ahr. in water. If quenched at this temperature the alloy is more malleable and stronger, 
for ih/B reason that the hard and brittle constituent Cu4Sn has been prevented from form- 
ing. This oonstitoftnt does not form unless tl&e alloy is cooled in the air to below 990 
deg. fahr. This important fact is taken advantage of commercially in modifying the 
properties of oopper-tia alloys in a way analogous to the annealing treatments of steel. 

Btrtngth of Bro&M at Varioofl Temperatures in per cent of the 
atrensth at 68 deg. fahr. averages about as follows: 

Tsmperature, deg. fahr 212 392 572 752 932 

Tensile strength (relative} 101 94 57 26 18 

Bell Metal alloyn are alloys of copper and tin containing from 15 to 25 
per cent of tin. The' higher the tin content the more brittle the alloys be- 
eome, and the higher the note which they will produce. 



Oopper-Zinc Alloys (Brasses) 

The term brass is properly applied to alloys of copi>er, the properties of 
which are modified chiefly by the' addition of sine up to approximately 42 
per cent. Many of the commercial brasses oontain small percentages of tin 
and lead, and certain well-known alloys belonging under the general classifi- 
cation of brass have their properties modified by the addition of iron, man- 
ganese and aluminnm. Alloys containing approximately 50 per cent each of 
oopper and sine are known as braslng solders. 

Industrial Brass may be divided into two classes, namely, cast brass 
and wrought brass. 

Cast Brass varies in its sine content from 30 to 40 per cent. The most 
desirable mixture contains 65 per cent copper and 35 per cent sine. The 
alloy is given hardness by the addition of a small percentage of tin. The 
straight alloy is soft and ductile and drags severely under the tool, but the 
addition of 1 to 2 per cent of lead allows it to be machined freely, producing 
short chips. 

There are two classes of jrellow brass ingots made from scrap on the market 
intended for casting purposes : 

1. Ingots produced from rod chips, which when melted down make a very 
satisfactory casting brass; it contains little tin, has the necessary hardness 
and fluidity in casting, enough lead to insure free machining, and is practi- 
cally free of iron. A typical analysis is 63 per cent copper, 2 per cent iead, 
no tin, balance sine. 

2. Ingots made from miscellaneous yellow brass scrap and containing 
from about )^ to 2 per cent of iron, and often lead and tin in excess of the 
amounts desirable for good working; used only for cheap classes of work, such 
as plumbers' ferrules, etc. 

U. 8. Navy Bpeeffications (Adopted, 191T) for Naval Brass Castings. Castings 
shall be made of raw materials of a high grade; dean high-grade scrap may be used pro- 
vided resultant alloy is in accordance with percentage chemical requirements, which 
are: Copper, 60-65; tin. 0.5-1.5; rinc, remainder; iron and aluminum each (max.) 
0.5; lead (max.), 1.0; normal proportiona, 62-1-37. 



BSASSEa 

Tibl* 14. Prapwtie| of Varioiu Coppw-Zlne AUoji 



TiK pie» for eomjKHrioD ta>ti nan 3 in. lODS ud H.iH' dwm. 

Onaal l»qull»iM»Bt for AUltr Outliis*. Twt «oupotti dull be pravided tof 
«feebcaitiD( or lot of rattinfi, a lot bfliD|DDiutru«lftAcompriiiDimU the caMin^ pound 
feoB «M tadic or crudible of metal. At least two teat coupona shall be cait attached 
lo laeh raatins weishiii( SSO pouodi « more aa delivered from the foundTy. The 
these teat ooopon* ahall be 3 inchu by 1 Inch by S inohca loii«. and shall 
Lrt of tb« oastinc and not cetcd thereto. 

ih IsH tlua 390 pounds eseb s* delivered from the foondiT. coupons 

' • last eaatini pourwl from each lot of not 

. insh in diameter br ioohea loaf. 

Casting ihaO be in aooordanoe vith detail ipeeificatioiu and shsU 

Be BUDd, clean, and free from blowboles, porous plaoee, orsoks, eeBrviTatkon to such ao 

■Rent aa to result in a tpottod mirtaoe aftor machiziins, sc olhei iniuiioua defscta. 

Tnstnr*, The color of llie fracture and the grain of the metal shall be uniform 



58 



NON-FERROUS METALS AND ALLOYS 



and fittiniDB; nil and ladder atanchiomt; bracket^, oUps, etc.* for stowage purpoeea; 
fittings for canopy frames; all bra^s valves and fittings of ventilation ssrstem (except 
working parts); belaying pins, tarpaulin hooka, brass hatch and door fittings, brass- 
pipe flanges. Valve hand wheels, hnndrail tittincs, ornameni-al and miscellaneous cast- 
ings and valves in water chests of condensers. 

V. 8. Vayy 8p«eifle«ttoiui (Adopted, 191T) for Commarcial Brass Castings: 

The percentage chemical requirements are: Copper (min.). 62; sine (min.), 30; iron 
(Max.), 0.76; lead (limits), 1.5-3; nickel, tin, or both, remainder. 

Marino Uso. Material is suitable for same and number plates, cases for instnimenta, 
oil cups, distribution boxes, ete. 

Wrooglit Brass. There is some confusion of nomenclature in relation to 
wrought brass. The names in 4^he table on p. 57 are the usual commercial 
names in the U. S. In addition an alloy of 85 copper and 15 zinc is called 
rich low brass* The nomenclature is entirely different from that in use in 
England. 

Hot-workixig Brass. Alloys containing approximately 56 to 62 per cent 
copper and the balance sine beoome plastic when heated to redness and are 
capable of hot working. The most widely used and known alloy within 
these si>ecifications is Munti metal (60 per cent copper and 40 per cent 
sine), which was formerly largely used for ship sheathing, it being claimed that 
this alloy is corroded just sufficiently to prevent the attachment of barnacles. 
The alloy is also used for many purposes in which a hard sheet brass is desir- 
able; According to Bengough and Hudson, it should not be rolled or extruded 
at a temperature below 1 100 deg f ahr. It is hardened by quenching. Tensile 
strength, about 55,000 lb. per sq. in. 

V. 8. Hayy 8p6eifleations (Adopted, ItlC) for Cast Munts Metal: Percentage 
chemical requirements: Copper, S9-62; sine, 38^1; lead (max.), 0.6. No physical 
requirements are specified. 

U. 8. HaTy 8peeilleations (Adopted, ItiS) for Boiled Munts Metal Bars, 
nates, 8lMets, and Shapes: (Chemical requirements the same as Cast Munts Metal 
except iron (max.) 0.2 per cent. Physical requirements: tensile strength, lb. per sq. in., 
46,000; elastio limit, lb. per sq. in., 25,(X)0; elongation in 2 in., min., 25 per cent. Toler- 
ances same as brass sheet. 

Marine Use. Rolled munts metal is suitable for bolts and nuts not subject to the 
action of salt water, sheathing bottoms of wooden boats, etc. 

V. 8. Bavy 8peeifleatlons (Adopted, 191S) for Brasing Metal (More properly 
ealled Flange Metal) call for the following percentage chemical composition: Copper, 
84 to 86; sine, remainder. Iron must not exceed 0.06 per cent and lead 0.3 per cent. 

Marine Use. This material is suitable for flanges for copper pipe and other fittings 
that are to be brased. 

v. 8. Navy 8peclfloatlona (Adopted, 1918) for BoUed Baval Brass Bars, Shapes. 
PUtes, and Bods (Abridged): 

•Scrap shall not be used in the manufacture of rolled naval brass, except such as may 
accumulate in the manufacturers' plants from material of the same composition of their 
own make. NoUl Thi» claiiM appears on all Navai Rolled Alloy Speeifieationa. 

The chemical and physical requirements are: Copper 59-63 per cent; tin 0.5-1.5 per 
cent; sine, remainder, iron (max.), .0.06 per cent; lead (max.), 0.2 per cent. 

Rods 



Diameter or thickness 
Inch 



Oto H 

Over M to 1 

Over 1 ! 



Minimum 

tensile 

strength 

Lb. per sq. in. 



60.000 

S3.000 
54,000 



Minimum 

yield 

point 

Lb. per sq. in. 



Minimum 

donation 

in 2 inches, 

per cent 



Bend 120 
deg. eold. 



27.000 

26.000 
25.000 



35 

40 

40 



Radius equal 
to thickness. 
Do. 
Do. 



BRA8SBS 



59 



Sh»p«ft 



Diaqieter or thfeknaw 



MinuDum 

teoaild 

strength 

Lb. per aq. in. 



MininMim 

yield 

point 

Lb. per aq. in. 



Minimim ! 

elongation , Bend 120 deg. 
in 2 inchee, eold 

per cent | 



All 



56.000 



40 per cent, of 

tne tensile 

strength. 



30 



Radius equal 
to thickness. 



Plates 



to H in. up to 30 in. 
• width 

Oto H in. above 30 in. 

width 

Over H in 



T 



56.000 

54.000 

56.000 



28.000 

27.000 
254X10 



30 

35 
35 



Radius equal 
to thickness. 

Do. 
Do. 





Tubing 






Wan thickness 
Inch 


60,000 


36.000 
30.000 N 


22 
25 
27 




OtoH 




Orer « to >i 

Over Vi 


55.000 
50.000 


• 











Tolsranest. (o) No excess weight will be paid for, and no single piece that weighs 
more than 5 per cent above the calculated weight will be accepted. (6) Plates and 
ih«ets shaO not vary throughout their length or width more than 6 per cent for sheets 
cr plates under 48 in.. 7 per cent between 48 and 60 in., and 8 per cent when over ' 
60 in. wide. 

Ifarine Um. The material is suitable for parts especially 8ub|eet to corrosion as by 
nit water: Bolts, studs, nutf, and turnbuckles: rolled rounds, used principally for 
propeDer blade boitak air pump and oondenser bolts and parts requiring strength and 
ineorrodibifity; and pump rods, tube sheets, supporting plates, and shafts for valTea 
m water heads. 

V. i. Mtsff BiMemeAUon* (AdtQpUd, 1917) tor CommareUl Btma lor Eoda, 

Ban, Bhapai, 8h«ett, ajid Platas require Copper. 50-63 per cent; tin (max.), 
1-5 per cent: sine, 32-41 per cent; lead (max.), 3 per cent; iron (max.). 0.2 per cent. 
The material shall be clean, smooth, of uniform quality, color, and aise, and shall be 
free from all injurious defects. Physical tests of this material are not required. 

Marine 17m. This material is suitable for liners, trim, etc. (sheet brass) ; hand rails, 
distributing oil tubes and water pipes (brass pipe), for trim and purposes where strength 
Md incorrodibility are not required (rod). 

V. t. KftTy 8p«eiflestioiii (Adopted, ItlT) for Hoetrteal Afypllaneea (CMtlngi 

tor) require copper, 80-88 per cent; tin (max.), 2 per cent; sine, remainder; Iron (max.), 
0J5 per oent; lead (max.), 2 per oent. 

Htfliie Vm. This material is suitable ^or eleetrieal fittings such as junetion boxes* 
nntehfis. distribution boxes* eonneotion boxes, water-tight bells and bussers, eto. 

Xodliled Hot-world&( Brass is brass the properties of which have been 
somewhat altered by the addition of tia and iron. Two alloys of this nature 
which are largely used are Tobin bronse and Delta metal. 

Tobin BronjM is a proprietary alloy of the American Brass Co., containing, 
■coording to published analyses, 58 to 60 per cent of copper and about 40 
per cent of sine, the remainder being iron, tin and lead. It is made in the 
fonn of 8heet« and plates (^e ^ ^ ^Q* thick), rods (up to 7 in. diam-)« rectangu- 



60 NON-FERROUS MSTALS AND ALLOYS 

lar bare and seamless tubes. At a efaerry-red heat is can be readily forg«<L 
It is especially resistant to corrosion, and is used largely in naval work. 
Tensile strength of rods larger than 1 in. in diam.. 60,000 lb. per sq. in. 
(62,000 for snuiller rods); minimum yield point, ^ X tensile strength; elon- 
gaUon in 2 in., rods U^ger than 1 in., 28 per cent (25 per cent for smaller 
rods); compressive strength, 170,000 to 180,000 lb. per sq. in. These proper- 
ties make it adaptable for a wide variety of engineering purposes where a 
strong, reliable material is required. Weights of sheets and rods are iH 
per cent lower than the weights for brass rods and sheets in Tables 3 and 5. 

Delta Metal is similar in composition and properties to Tobin bronze, 
except that it carries from 1 to 2 per cent of iron. It is manufactured by the 
Phosphor Bronse Smelting Co., and is furnished in sheets and rods, j 

Cold-working Brass. For tubes, cartridge cases, wire drawing, etc., the 
standard alloy contains 70 per cent copper and 30 per cent sine; this alloy 
posseeaes considerable strength and great ductility; higher-copper alloys have 
still greater ductility. This alloy can be worked cold, and when intended 
for rolling or drawing is cast into a mold of such sixe and shape that the alloy 
may be formed into its finished shape with as little working as possible. In 
wire drawing, ingots of suitable sise are first rolled into rods, these being 
finally drawn into wire. Spring brass has the composition copper 72, 
sine 28, or copper 66^, sine 33 H. This alloy hardens under the effect of 
working and must be frequently annealed in order to correct this condition 
and allow further reduction. After each a-nn^aJltty process the brass must 
be washed with acid to rid the surface of oxide. The temperature of an- 
nealing is an important matter and must be carefully observed. Anneal- 
ing below 536 deg. fahr. has practically no effect. There is a particular 
temperature at which the best results are obtained for each alloy, depending 
on the amount of hardening the alloy has undergone. At 620-650 deg. fahr. 
there is a marked softening of 70-30 brass. The maximum effect of annealing 
is reached at 1400 deg. fahr. Above this temperfiture the brass ia burnt. 
Alloys oontaining small pereentages of tin and lead can be raised to higher 
temperatures than those not containing these metals without being burnt. 

Lead and tin are frequently added to cold-working brass alloys, in order 
to confer certain properties. Load is added to facilitate machining, chips 
of a leaded brass leaving the tool easily, as they are short and brittle. Lead 
is mechanically mixed in brass and therefore breaks up the continuity of the 
structure. In brass containing an excess of lead, the lead is present in solid 
solution, rendering the alloy more brittle. Turnings from brass which does 
not contain lead come off in long, tenacious curls. Leaded brass must bo 
rolled cold because it is *' hot-short.*' The best alloy is one which contains 
60 per cent copper, 38 per cent sine and 2 per cent lead. This has an aver- 
age tensile strength in the rolled form of about 60,000 lb.; elongation, 15 
to 20 per cent; reduction of area, over 50 per cent. Tin is often added to 
brass to inerease the hardness and to add to the resistance of the metal to the 
corrosive action of sea water. Antimony and bismuth are detrimental im- 
purities. Arsenic is considered beneficial by some makers. 

U. 8. Kmff gpeeifications (Adopted, ItlS) for Admiralty Metal call for the f oK 
lowing percentage chemical oompoeition: copper, 70; tin, 1; sine, remsinder; iron 
(max.), 0.06; lead (max.), 0.075. 

Marine ITse. This material is suitable for condenser tubes, distiller tubes, feed 
water heater tubes, and evaporator tubes. 

For weights of brass sheets and plates, see p. 44. For weights of 
round and square brass rods, see p. 61. 



BSASSES 



ei 



T»bU 15. Weights of Bound and Bquare Brass Bods 

(Lb. per lin. ft.) 






Mi 

H 

Me 

H 

f1« 

H 

M« 

)4 

fit 

H 



O 



s 



0. 

0. 
0. 

a. 

0. 



.otr3 

0458 
1030 
1810 
.2830 
.4070 
0.5550 
0.7240 
0.9170 
r.l300 



0.0144 
0.0576 
0.1300 
0.2300 
0.3600 
0.5190 
0.7060 
0.9220 
l.fTDO 
1.4400 



B 
i! 

Q 



I 
IMe 

m 



a 

o 



1.37 
1.63 
1.91 
2.22 
2.55 
2.90 
3.27 
3.67 
4.09 
4.53 



1.74 
2.08 
2.44 



$3 
24 
69 
16 
67 
20 
76 



nu 
mt 

\H 



9 

o 



4.99 
5.48 
5.99 
6.52 
7.07 
7.65 
8.25 
8.87 
9.52 
10.20 



s 



6.36 

6.97 

7.62 

8.30 

9.01 

9.74 

10.50 

11.30 

12.10 

13.00 



o 



l»fi« 


10.9 


2 


11.6 


2H 


13.1 


2H 


14.7 


2H 


16.3 


2Vi 


18.1 


296 


2D.0 


2H 


21.9 


2Ti 


24.0 


3 


26.0 



13.9 
14.8 
16.7 
18.7 
20.8 
23.1 
25.4 
27.9 
30.5 
33.2 



Table 16. 



Apjutxdmate Weight of Brass Wire 

(Lb. per 1000 Ft.) 



B.AS. 


Weight 


B.ftS. 
g^e No. 


Wei^t 


B.ftS. 
gage No. 


Weight 


B. AS. 
gage No. 


Weight 


OOQO 


610.0 




47.60 


19 


3.710 


30 


0.2900 


000 


483.0 




37.70 


20 


2.940 


31 


0.2300 


00 


383.0 


10 


29.90 


21 


2.330 


32 


0.1820 





304.0 




25.70 


22 


1.850 


33 


0.1440 


1 


241.0 




18.80 


23 


1.470 


34 


0.1150 




191.0 




14.90 


24 


1.160 


35 


0.0908 




152.0 




11.80 


25 


0.923 


36 


0.0720 




120.0 




9.38 


26 


0.732 


37 


0.0571 




95.4 




^a 


27 


0.581 


38 


0.0453 




756 




5.^ 


28 


0.460 


39 


0.0359 




60.0 


« 


4.68 


29 


0.365 


40 


0.0285 



He»t-tr«atment of Brass 

The physical propertieB of annealed brass vary according to the temperature, and to 
some extent to the time i n which the annealing has been done. When annealed at 650 to 
750 deg. iahr. under ordinary annealing conditions, brass stripe containing two parts 
copper and one part rinc may have a tensile strength of about 56,000 lb. p^ sq. in., with 
dragation in 2 in. of 40 per cent. When annealed at 1300 to 1400 deg. fahr., 
voder similar conditions, they may have a tensile strength of about 40,0001b. per sq. in., 
with elongation In 2 in. of 65 per cent. The process of annealing relieves those 
iaternsl strains which result fh>m cold-working the material. Annealing of cold-worked 
brsa is acoompanied by a r^-distribution of the mdeculee resulting in the formation of a 
new oystalline structure. The average minimum temperature required to effect re-crys- 
tsBisation of the hrsnsis in one-half hour is 750 deg. fahr. The sixe of the grain is 
toughly propCRrtaonal to the temperature within the safe annealing range (750-1400 deg. 
faltf.), and for a given time, temperature and alloy the grain sise is constant. Under 
tlisn conditions the grain siae has a definite relation to the physical properties; also, grain 
■w has considerable influence on resistance to corrosive action. Impurities such as iron, 
niekd, etc., retard the growth of the grain size and render necessary the use of a higher 
lemperature to secure a given grain sise than with pure brass. 

AttBealing removes, to a very great extent, the liability of brass to crack or disintegrate 
on proloBgad exposure under unfavorable conditions. For this reason the best practice 
nqoirss that in structural work all material for tubes, rode, bolts, etc., shall be lightly 
annealed. 



62 NON-FERROUS MBTALS AND ALLOYS 

Special BronsM and BratMS 

Casting ManiruieM Bronxe. Manganese bronze ia in reaUty a bran, 
oonsisting largely of copper and sine. The term bronse, however, has been 
generally applied to it for many years. It has a light yellow or golden oolor/ 
It is very much stronger than the ordinary brassss. Manganese is 
simply used as a deoxidizing agent, and the finished alloy very often contains 
but mere traces of ii. 

Manganese bronze is now one of the standard alloys on the market and is 
highly rsoonunended for propellers which are used in salt water, both 
because of the resistance of the metal to the action of salt water, and its 
remarkable strength and ductility. It is also a favorite alloy for many cast- 
ings used in automobile construction. In casting, large risers are necessary, 
due to the high shrinkage of the alloy. 

The A. 8. T. H. Speeifloations for Manganese Bronse Ingots having notched 
flat bottoms approx. 3X2^ in. wide by 12 in. long, call for the following pertontage 
chemical ooropomtton: Copper, 53 to 62; zinc, 36 to 45; aluminum, 0.05 to 0.5; lead; 
not over 0.15. Ultimate tensile strength not to be leas than 70,000 lb. per. sq. in., 
elonfi^ation' in 2 in., not less than 20 per cent. Test specimen to be turned to 0.5 in. 
dism. and 2 in. gage length, from a piece cut from one corner near bottom of ingot. The 
compressive strength is about 120,000 lb. per sq. in. 

The U. 8. Navy 8peciflcatiom (Adopted, 1917) for Manganese Bronze Ingots 

from 9 in. to 12 in. long call for the following percentage chemical composition: copper, 
55 to 62; sine, 38 to 42; tin and aluminum, each, not over 1.5; manganese, not over 3.5; 
iron, not over 2, and lead, not over 0.2. The sum of the specified elements shall equal 
09.9 per cent. Tensile strength not to be less than 70,000 lb. per sq. in,; elongation 
in 2 in., not less than 20 per cent. 

Marine Use. This material is suitable for propeller hubs; propeller blades; enipne 
framing; compoBition castings requiring great strength, such as main gearing in steering 
engine, worm wheels in windlass and where great strength and resistance to corrosion 
are required. 

TS. 8. NaTy 8peoiflcations (Adopted, 1S17) for Oast Manganese Bronss call 
for the same elongation and chemical requirements as Manganese Bronse ingots except 
that the sum of the specified elements shall equal 00.8 per cent. The minimum tensile 
strength allowed, 65,000 lb. per sq. in. Two grades are specified, Grade A, made from 
virgin materials, and Grade B, from materials not specified. 

Marine Use. Grade A is suitable for propeller blades, propeller hubs, engine framing, 
and in general for all castings requiring great strength and purity of material. Grade B 
material is suitable for all manganese bronse castings where Grade A is not specifically 
designated. 

U. 8. Navy Specifications (Adopted, 1917) for EoUed Manganese Bronae call 
for the following percentage chemical composition: Copper, 57 to 60; tin, 0.5 to 1.5; 
sine, 40 to 37; iron, 0.8 to 2; lead (max.), 0.2; manganese (nuu.), 0.3. Tensile strength 
not to be less than 72,000 (70,000) for stock 1 in. and below (above 1 in.) and the elonga- 
tion in 2 in. 30 per cent; yield point is 50 per cent of tensile strength. Bars must stand 
being bent cold through an angle of 120 deg. and to a radius equal to the diameter or 
thickness of the test bar. 

Marine Use. Material is suitable for rdled round ban requiring great strength 
where subject to corrosion and salt water, valve stems, propeller blade bolts, air pump 
and condenser bolts, and parts requiring strength and inoprrodibility. 

Wrought Manganese Bronse. Manganese bronse is capable of being 
wrought similar to Muntz metal, Delta metal and Tobin bronze, except that 
it extrudes with great difficulty. 

Tensilite, a high-strength bronze manufactured by the American Man- 
ganese Bronze Co., is stated to have the following physical properties: Ten- 
sile strength, rolled or forged, 120,000 lb. (cast, 105,000); elastic limit, 
75,000 (60,000) ; elongation in 2 in., 18 per cent (15) ; reduction of area, 22 



SPECIAL BRONZES AND BRASSSS 



68 



per cent (20); eUustic limit ib compression. 70,000 (60,000); permanent set 
under a load of 100,000 lb. per sq. in., 0.015 in. (0.020). 

^ |iiiwi«M«ft Bronso is an alloy of copper and aluminum, containing up to 
1 1 per cent of the latter metal. Some years ago it was a strong competitor of 
manganese bronxe, and in general it may be said that 1 1 per cent aluminum 
bronse (the strongest mixture) has a somewhat higher tensile strength than 
manganese bronse, but a lower percentage of elongation. It was found that 
manganese bronse was more easily handled in the foundry and could be better 
depended upon; and as it could be produced more cheaply than aluminum 
bronse, it naturally became the more popular alloy for resistance to severe 
stresses. By the addition of titanium good solid castings of aluminum bronse 
can be obtained. Aluminum beyond 11 per cent mak^s a brittle bronse 
which m baxd to work. Aluminum bronse can be readily soldered. 

Dagger's tests on copper-aluminum alloys yielded the following results: 



AluBunum. 


Specific 


Average tdnitle 
strength, lb. per sq. in. 


ElongatioD. 


per cent 


gravity 


per cent 


II OQ 


7.23 


95,000 


8 


10 00 


7.m 


82.000 


14 


750 


S.OO 


61.000 


40 


500 


8)7 


37.000 


40 


2.50 


8.69 


31.500 


SO 


1 25 




27.000 


55 









Aluminum BraM is a copper-sine alloy containing up to 3 per cent of 
aluminum, and a very valuable series of alloys is thus produced with a wide 
variation of tensile strength and elongation. The alloys ire quite analo- 
gous to the so-called manganese bronses, and are often substituted for them. 
Aluminum brass, as made by the Aluminum Co. of America, has a tensile 
strength of 40,000 to 50,000 lb. per sq. in. (elastic limit, 30,000). and an elon- 
gation of 3 to 10 per cent in 8 in. ^ . /. . 

Aluminum, when added in the form of aluminlsed sine to brass in quantities 
up to 1 per cent, makes the brass flow freely, and the resulting castings have 
smooth surfaces and are free from blowholes. Added in larger quantities (up 
to 10 j>er cent) it imparts increased strength to the castings. 

V, 1. Havy Speeilleations (Adopted, 1018) for Aluminum Bronse Ingots and for 
Cast Alomlnum Bronse require the following percentage chemical composition: 
Copper, 85 to 87; iron, 2.5 to 4.5: aluminum 7 to 0; tin (iflax.). 0.5; max. sum of impurities 
jnchMJing lead, nnc, etc., 0.1. Only the beet grades of virgin materials, or scrap of known 
and approved compoeition, shall be used in the manufacture of aluminum bronse ciist- 
ings and ingots. 

Aluminum bronses differing from the above composition in that they may contain 
niekel or deoxidising agents such as vanadium, titanium, etc., will be considered pro* 
vided that a complete chemical analysis is given by the manufacturer and that other 
r e qui rements are complied with. The sum of aluminum, copper and iron shall not be 
Icfls than 90 per eent. 

The foflowing minipium physicalpr operties are required: tensile strength, 65,000 lb.; 
yield point, 36,000 lb. ">' 

Marine IFse. Suitable for use where a non-corroding material possessing great 
strength and hardnees similar to manganese bronse and where good bearing qualitiee 
•ombined with strength are desirable as for struts, rudder frames, propeller blades, 
worm wheek, gears, etc. 

U. Si KaiT BpeetteattoBS (Adopted, 1018) for Boiled Aluminum Bronse call 
fcxr the foUowing peroeotage chemical composition: Copper, 85 to 87; iron, 2.5 to 4.5; 
tin (max.), 0.5; aluminum, 7 to 0; max. sum of impurities including lead, sine, etc., 
0.1. Only the beat grades of virgin materials, or scrap of known and approved com- 
positioB shall be used in the manufacture of rolled aluminum bronse. 



64 



NON'FBRROUS METALS AND ALLOYS 



Aluminum broniea differing from the above compoeition in that they may contain 
deoxidising agents such as vanadium, titanium, etc., or nickel, will be considered pro- 
vided that a complete chemical analyaiB is given by the manufacturer and that the 
other chemical requirements are complied with. The sum of aluminum, copper and 
iron shall not be less than 99 per cent. 

All aluminum bronie bars, sheets, plates and shapes shall be hot rolled, drawn or 
extruded, but m^y be finished cold. 

The pbyeical properties shown below arc required : 



U. S. Nayy Physical Bequireihanti for Rolled Aluminum Bronio 

Rods and Bars 



Diameter or thickness, 
in. 

• 


Tensile 

strength, 

minimum 

lb. per 

sq. in. 


Yield 

point, 

minimum 

lb. ^ 

sq. m.. 


Elonga- 
tion in 2 

in., 
minimum 
per cent 


Cold bend. 120 deg. 


Up to ^i in., inc 

Over >^ to 1 in., inc . . 
Over 1 m 


80,000 

75,000 
72.000 


40.000 

37,500 
35,000 


30 

30 
30 


Radius equal to diameter 
or thicknMS. 

Do. 
Do. 







Shapes 



Diameter or thickness, 



m. 



Tensile 
strength, 
mini- 
mum 
lb. per 
sq. in. 



Yield 
point, 
mini- 
mum 
lb. per 
sq. in. 



Elonga- 
tion m 
2 in., 
maxi- 
mum 
per 
cent 



Elonga- 
tion m 
8 in., 
mint- 
mum 
per 
cent 



Cold bend. 120 deg. 



All 

Oto H in. ^up to 30 in. 

width) 

to H in. (over 30 in. 

width) 

Over J-s in 



75,000 i 37,500 



30 



25 



Radius B thickness. 



Shbbts and Plates 



80.000 

76,000 
75.000 



40,000 

39.000 
37.500 



30 

30 
30 



25 

25 
23 



Radius equal to thick- 
ness. 

Do. . 
Do. 



Marinfl Um. This material is suitable for rolled rods and bars requiring great 
strength where subject to corrosive action, valve stems, propeller blade bolts, air pump 
and condenser bolts, etc., and for purposes requiring great strength combined with good 
beating qualities, sueji as slide liners, etc. 

V. S. Nayy 8peciflcation8 (Adopted. 1916) for Vanadium Bronse Castlixffg 
call for the following percentage chemical composition: Copper (min.), 61; tin, in- 
cluding vanadium, lead, bismuth, aluminum, and nickel (max.), 1; zinc 37 to 39. Ten- 
sile strength, 55,(XX) lb. per sq. in.; yield point 22,500 lb. pccsq. in.; elongation in 2 in., 
26 per cent. 

Casting Bed Brass. The term red brass is applied to all alloys oontaining 
a sufficient amount of copper to be red in color, with the exception of those 
reddish alloys of copper and zinc carrying approximately 45 per cent of sine 
and 55 per cent of copper: manganese bronxe, aluminum bronae and ahiminuni 
brass. Red brasses usually carry upward of 75 per cent of copper and varying 
amounts of tin, sine and lead. These alloys, because of their ease of machin- 
ing, ease of casting and red color, are used for steam fittings, ornamental cast- 



SPECIAL BRONZES AND BRASSES 66 

in^, miflceUaneous brass trimTningw, hardware, etc. Different alloys for 
varioiis purposes have the following peroentage oompositionB: 

Copper Tin Lead Zino 

Vslve metal* 85 5 5 .5 

Steam metal 86 8 3 3 

Gas cocks 76 2 6 16 

PoUahiDc metal 87 *1 12 

Braanc metal 80 20 

* a A. E. a^^edfieatioii No. 27 f or U«hi eastiocs. 

Bed Bran Xncote made from wmnp, turnings, etc., are sold upon the 
market, subject to specifications with a variation of 1 per cent either way on 
the constituents, at a price below the cost of producing the same. composition 
from new metals. Thii mAt«rial U not tuitabla for Marine um. 

Phogphor Bronie in the wrought form (bare and plates) consists of up- 
ward of 96 per cent of copper and up to 4 per cent of tin which has been 
deoadiaed by sufficient phosphorus. A small peroentage of phosphorus 
can be left in the alloy, and adds to its hardness. Its qualities of toughness 
and great tensile strength, combined with resistance to corrosion and crystal- 
liaation, make it superior to German silver for exposed work. It has superior 
elasticity and can be furnished in wire and sheets to various tempere for use 
in m^iring gprlngg. 

IT. S. Wavy Bpedfieatlons (Adopted, If It) for Boiled or Drawn Phosphor 
Bronse call for the foUowing percentage chemical compoeition: Copper (min.)i 94; 
tin (min.), 3.5; sine (max.)* 0.3; iron (max.). 0.1; lead (max.)* 0.2; phoephorua, 0.05 
to 0.5. The following physical properties are required for rode and bare: Tensile 
strength, lb. per aq. in., up to H in. diam., 80,0(X); H ii^ to 1 in., 60,000; over 1 in.. 
55,000. Yield point, lb. per sq. in., up to H in., 60,000; H in- to 1 in., 40,000; oVer 
1 in., 30/XX). Elongation in length of 4 times diam., up to }^ in., 12 per cent; H in> 
to 1 in., per eent in 2 in., 20; over 1 in., per cent in 2 in., 25. 120 deg. cold bend test 
on radius equal to thickneaa. Phsrsical properties for sheets and plates, spring temper. 
Tensile strength, lb. per aq. in., 00,000; jrield point and elongation not specified. For 
sh^ts and plates, medium temper: Tensile strength, 60,000; yield point, 25,000; 
elongation in 2 in., 25 per eent; 120 deg. cold bend test around radius equal thickness. 

Marine Use. Rod material is suitable for bolt material, pump rods, valve stems, 
valves, and objeets exposed to action of salt water. Medium temper sheets are suitable 
for valve discs, etc Spring temper sheets are suitable for electric contacts. 

Cggt Phogphor Bronie (commercially known as "B" grade) contains 
from 88 to 92 per cent copper and from 8 to 12 per cent tin. To get the best 
results, just enough phosphorus is used to thoroughly cleanse the metal of 
oxides,- none being retained in the finished product. The American Man- 
ganese Bronse Co. give for cast phosphor bronze, tensile strength, 25^40,000 
lb. per sq. in.; elastic limit, 18-30,000 lb. per sq. in.; elongation in 2 in., 
42 per cent; reduction of area, 32 per cent. To obtain the best results this 
alloy should contain no lead or sine. It is a particularly desirable metal for 
gears, being hard and tough and having a low rate of wear. 

U. t. Maty Spedfteattons (Adopted, IMT) for Cast Phosphor Bronse specify 
two grades. Grade No. 1 having a tensile strength, of lb. per sq. in., of 45,0(X) and elonga- 
tion in 2 in. of 20 per eent. Grade No. 2 has a tensile strength of 30.(XX) and elongation 
of 15 per cent. The peroentage chemical compoeitions are copfter, 85 to 90; tin, to 
11; Grade No. 1 (Grade No. 2), sine, 4 (remainder) ; iron (max.). 0.06 (0.1); lead (max.), 
0.2 (1.0); phosphorus (max.), 0.5. Proprietary bronzes differing from the above are 
aeeeptaUe when approved by the Bureau of Steam Engineering. 

Marine Use. This material is suitable for fittings exposed to the action of salt 
water, for gears, driving and main nuts of steering gears, and castings for other parts 
whifdi require sU«ngth eombined with good bearing qualities and inoorrodibility. Grade 
1 should not be speoilled where Grade 2 may answer. 

5 



14 


24 


12 


32 


11 


S2M 


10 


35 


7 


36 



66 NON-FERROUS METALS AND ALLOYS 

SPECIAL ALLOTS 
Copper-Nickel Alloys 

Cupro Kickel, or Benedict Nickel, is au alloy of 85 per cent copper 
and 15 per cent nickel. U. S. Nayy Specifications (Adopted, 1917) 
allows 1 per cent variation from this formula. This material is suitable for 
tubes for condenser distillers and feed-water heaters. The addition of a small 
percentage of manganese or magnesium greatly facilitates the proper working 
of the alloy in ingots and under rolls. Constantan (60 per cent copper, 40 
per cent nickel) has a very low tem>perature coefficient and is used for elec- 
trical resistance purposes. 

Oerman Silver is an alloy of copper, nickel and zinc. It is very ductile 
and can be rolled, hammered, stamped and drawn. At the same time it is 
hard, tough and not easily corroded, and above all poaseeeaa the valuable 
property of being white. It is softened by annealing. 

Hiorns gives the following table showing the conxposition of various quali- 
ties of German silver made by the best makers in Birmingham, England. 
These different alloys are sold under the trade names indicated. 

Ck>mpo8ition, per cent Composition, per cent 

Name Copper Nickel Zinc Name Copper Nickel Zinc 

£xtra white metal ... 50 - 30 20 Seconda 62 

White metal 64 24 22 Thirds 56 

Argucoid 48^ 20H 31 Special thirds 56^i 

Best best 50 21 29 Fourths 55 

Firsts or best 56 16 28 Fifths, for plated goods . 57 

Special firsts 57 17 27 

Hiorns states that alloys containing less than 16 per cent of nickel should 
contain 30 per cent of zinc in order to give the best results; while with alloys 
containing more than 16 per cent of nickel, the quantity of zinc should be less 
than 30 per cent. The impurities found in German silver are iron, lead and 
tin. Iron increases the strength, hardness and elasticity, and makes the alloy 
whiter. Tin renders the alloy brittle and unfit for rolling. It also gives the 
alloy a decidedly yellow color. Lead does not enter the alloy but simply 
remains mechanically mixed, and therefore should be added if the alloy ia 
intended for casting and subsequent working. 

U. 8. Navy Specifleations (Adopted, IftlT) for Oerman BUver call for the fol- 
lowing percentage chemical composition: Copper 60 to 67; sine, 18 to 22; nickel 
(min.) 15; iron, lead and sulphur, trace only. Fracture test may be made to deteroune 
soundness; the grain must be uniform throughout. 

The weight of German silver wire made by the American Brass Co. and 
containing 18 per cent nickel is 2.5 per cent lower than that of copper wire 
of the same size and length; of 30 per cent nickel it is 1.8 per cent less. 

Monel Metal is a natural alloy consisting of 68 to 70 per cent nickel, l}^ 
per cent iron, and the remainder copper. It is smelted and refined from ore 
mined in Canada without disturbing the proportions given. It is silver-white 
in color, takes a high polish and is highly resistant to corrosion, not being 
affected by atmospheric conditions, fresh or salt water, acid fumes or super- 
heated steam. Its specific gravity (cast) is 8.87, and its melting point 
2480 deg. fahr. Tensile strength: rods, 86,900 lb. per sq. in. (castings, 
78,240); elongation in 2 in.: rods, 40 per cent (castings, 38.5 per cent). 

n. 8. Kavy Speeifleationa (Adopted. 101«) for Boiled Monel Metal Ban, Platae« 
Bods, Sheets, etc., call for the following percentage chemical composition: Copper 
23; nickel, 60; with the following max. impurities: Iron, 3.5; aluminum, 0.5; man- 



SPBCIAL ALLOYS 



67 



gume, 3.6; and carbon and ailioon oombiaed, 0.8. The foUoninc tables i^ve tbe 
physicai requirements: 

B<Mlt and Bars 



Minimum 
yield point, 
lb. persq. in. 



Minimum 

ultimate 

tensile 

8trens:tfa , 

lb. per 

sq. in. 



Minimum 

elongation 

in 2 in., 

per oisnt 



RowidB and Mjuarea: 

Up to and tneludiM 1 in 

iM^in. to and includingl^ie in, 
lH !&• to and including z7<{g in.. . . 

m in. to and including 3>^ in — 

Over 3H in 

Rectaoglee 

Heugov 









40.000 


80X100 


25 


50.000 


85.000 


28 


45.000 


80.000 


30 


37.000 


75.000 


32 


40.000 


75.000 


32 


40.000 


75.000 


32 


40.000 


80.000 


32 



NoTK. — No material leaa than K in. in thickneee or diam. need be tested physically. 



SliMtf and Plates 




Tenttfe strength, minimum, 
lb. per sq. in. 


—  1 
Yield point, minimum, , 
lb. per sq. in. 


Elonsation, minimum 
in 2 in., per cent 


tfjOQO 


30,000 

1 


15 



Underweight Tolerances 



Note.— Material shall not vary throughout its length or width more than Tolerance 
the giren tolerance. ' per cent. 



Widths of sheeta or plates: 

Up to 48 in 

4r to 60 in 

Onr60in 



5 
7 

8 



Marfaie Um. This material is suitable for parts requiring strength or incorrodibility, 
nieh IS propeller-blade bolts, air-pump and condenser bolts, and pump rods. 

IF. I. "Kvwf Spedftcations (Adopted, 191C) for Cait Monal Metal call for the same 
ehenoeal requirements as given above for Rolled Monel. The physical requirements 
•re: Tensile strength, lb. per sq. in., 65,000; yield point. 32,500; elongation in 2 in., 
25per eent. 

Marina Um. This material is suitable for valve fittings, plumbing fittings, boat 
fitSints, propellcra, propdler hubs, blades, engine framing, pump liners, valve seats, 
■halt nuts and cape, and oMnpoaition castings requiring great strength. 



Aluminum Alloys 

Ahimlnum Alloys are extensively used in automobile conatruotion. 
The S. A. £. Specification No. 23 for aluminnm-oopper alloy calls for 7 to 8 
per cent of copper. This is a tough alloy having a tensile strength of from 
15,000 to 20,000 lb. per sq. in., and is especially adaptable for castings to with- 
stand severe shocks and stresses. Zinc produces the strongest alloys with 
aluminnm, the tensile strength running as high as 30,000 to 35,000 lb. per sq. 
ID. The S. A.. E. Specifications Nos. 24 and 25 are for alumlnuui-Blnc 
alloys, the former containing 12.5 per cent of sine and 2.5 per cent of cop- 



68 NON-FERROUS METALS AND ALLOYS 

per, and the latter 35 per cent of sine. The oopper-carrying alloy is tough, 
well adapted to forging, and easily machined. 

U. 8. NaTy Speeiflcationfl (Adopted, If IS) for Aluminum or Ught Alloy 
CaitlngB call for the following percentage chemical composition: Aluminum (min.), 
94; oopper (max.), 6; iron and silicon (max.). each 0.6; manganese (max.), 3. The 
physical requirements are: Tensile strength, lb. per sq. in., 18,000; elongation in 2 in., 
8 per cent. 

Marine TTie. This material is suitable for objects not liable to corrosion where 
lightness is desirable such as hand wheels, brackets, etc. It finds a special field in Ord- 
nance work. 

MagnaUum is an alloy of aluminum and magnesium containing from 2 to 
23 per cent of the latter metal. Specific gravity, 2.40 to 2.57; melting 
point, 1110 to 1290 deg. fahr. The alloy is lighter than pure aluminum, of 
much greater strength, and does not tarnish. Tensile itrength: Cast in 
chills, 42,000 to 64,0001b. per sq. in.; eand castings, 17,000 to 30,000 lb.; 
rolled, 28,000 to 35,000 lb.; stomped, 52,000 to 70,000 lb. 



meet of High Temperatures on the Physical Properties of Metals and 

. AUoys 

For a list of investigations on the effects of high temperatures on the 
strengths of metals and alloys, see M. Rudeloff, 1909, International Ass'n for 
Testing Materials. Most of the investigations have been limited in seope 
and have not dealt sufficiently with the cast and rolled metals at present in 
commercial use. An extensive series of tests by the Crane Co. on a wide range 
of metals and alloys is reported by I. M. Bregowsky and L. M. Spring, in 
The Valve World, Jan., 1913. The values given in Tables 17 and 18 are taken 
from this article, and are averages of from two to ten tests at each temperature. 



ANTI-FBIGTION ALLOYS (BXA&INO MXTALS) 

Antl-f fiction Allosrs are divided into four distinct classes: 1. Copper 
base, or those carrying over 50 per cent copper, usually from 65 to 80 per 
cent. 2. Tin base, or those containing over 50 per cent tin. 3. Lead 
base, or those containing over 50 per cent lead. 4. Zinc base, or those con- 
taining over 50 per cent rinc. Copper-base alloys are harder and stronger 
than white metsils having tin, lead or zinc bases, and are used for bearings 
which are required to resist heavier pressures. Frequently, however, com- 
pound metal bearings are used, having a copper-base bearing metal, for the 
backing and lines with an anti-friction metal usually of a tin or lead base. 

The copper-base metals operate with a lower coefficient of friction 
because they are harder, but they are more liable tx> heat under abnormal 
conditions because they are lacking in the necessary plasticity to conform to 
irregularities of the journals or of foreign particles which may become lodged 
between the journal and the bearing surface. If bearings could be main- 
tained in perfect adjustment, the harder alloys would give the most efficient 
service because of their low coefficient of friction and their lower operating 
temperature. The term anti-friction is generally applied to those alloys 
which have the highest coefficient of friction, namely, the soft white-metal 
alloys. 



BTBBNQTH OF METALS AT HIGH TKMPBRATVBISS 09 

Tabl* IT. T*ix«ll« TmU on Hatate miiI AUors SnhlMtvd t« Blsh 

T«mp«rAturM 

(TumAU atmistli uid nUMic timitln lb. per sq, bk.; fll<nu«tIon Qq 2 In.) uid fvliurtloii 



I) I 4M I 300 I OD I 7» I 9» I IDOO 



NOS-FSItBOUa METALS AND ALLOrs 



> A Btranc copper-tin broDH. > CodMIdIdc S par «Dt of ■lumiaum.  Hifbly 
Tegigtant lo loids; elude limit not deteTDiiiied. * CoDtsiiuDi 10 Mr cent of iluniiDum: 
•lutic limit not dBterminnl. > At £S0 d«. : 32.050, 19.300. 23.4 aod 31.6. • F«no-»ieaL 
lUed Lb eilra huvy valves over 7 io. ' RsuclBnid lOBllnibla by tpBoial prOMU uul lugd 
foe rins>. di>li> Kad triismingB for iroa nnd steel fitliiin for hifb tempantun*. • For 
*:r»ir pipe flttiosa (Cu, 77-80; 8o. i: Pb. 3; Zd. 13^1. • (Cu, 88; So, 10; Zn.S.) 
i*(Cu. 87: Sc, T;Pb. l:Zii. S.) At UOdeg: 17,200, 14.025, 4.4 and S. 2. " (Cu. 02.6; 
Pb, 2.6: Zn, 35.) " Rods, 30 per owC nisEel. » Bdwenier ■Usl, for valve •tami, 

The rate of wear fa gnatet in the hard alloys than in the soft alloys, because 
the particles of the hard alloys aplit oB m fterrice. whereas the partiolea of the 
soft alloy H become compressed or flattened out before being torn off. The bear- 
ins should be just auRicieiitly hard and strong to carry its load. If the bearing 
IB too Bof t it will roll out or ba pounded out, and will probably hiig the journal, 
■quesie out the oil Elm. become heated and be destroyed. 

The physical properties of some of the bearing metals, at determined at 
the Fenna. Ry. laboratories, are giTeii in Table 19. 
Noras OH T*B[.B la 

> BeuBiogr alml, 0.093 per cent cirboQ. ' Cumbcrlind oold-roUed elialtiiig, 0.0S3 psr 
eentnrbon. "Open-hearth Heel, 0.084 p«r cent eirbon. ' (Ni, 3.2B; V,0.46; C. 0.3S6). 
(rfllempetsd. •25pereent oicLel. '30peroent Dioknl; tiimedfroro 1 in. Io0.8ia, diam. 
' TuRwd to O.TE in. dism. from a ^in. bar. • Cumberland shiftini. 0.375 per unt car- 
bon. 'Annealed CCr. 0.4B: V, 0.146: C. 0.722). '• Rolled rod (tSi. 62.6; Zd, 35; Pb 
3.5). "Ewphaat (pboephar) broua (Cn, 05.5; 8a, 4; F, 0.31}. 



STRENGTH OP METALS AT HIGH TEMPERATURES 



71 



Tftble IS. Tonioaal TmU on MttaU and AU«y8 Bubjootad to Bigh 

Temperatures 

(Toratonal strength and elastio limit in in.-lb. per sq. in. Total twist in number of 

turns, with number of degrees exceaa. Test bars turned to 0.855 in. diam. 

from m-in. rods.) See notes at foot of opposite page. 



Materials 



Temperatures, deg. fahr. 



70 



385 



600 



800 



> Cold-rolled Shafting: 

Torsional strength . . 

ESbtstic limit 

Twist 

• Cold-rolled Shafting: 

Torsional strength . . 

Elastic limit 

Twist 

s Machinery Steel: 

Torsional strength . 

Elastio limit 

Twist 

• Kiekel-vanadium Steel: 

Torsional strength. . 

Elastio limit 

Twist 

• Nickel Steel: 

Torsional strength. . 

Elastio limit 

Twist 

• Nickel Steel: 

Torsional strength. . 

Elastic limit 

Twist 

Rolled Monel Metal: 

Torsional strength. . 

Elastic Kmit 

Twiai 

' Rolled Monel Metal: 

Toraional strength . . 

Ebstic limit 

Twist 

> Cold-roOed Shafting: 

Torsional strength. . 

Elastio limit 

Twist 

• Vana^um Tool Steel: 

Toiaional strengUi. . 

Elastio limit 

Twist 

M Rod Brass: 

Torsional strength. . 

Elaatio Umit 

Twist 

Tobin Bronse: 

Torsional strength. . 

Elastic limit 

Twist 

u Phosphor Bronze: 

Torsional strength. . 

Elastio Hmit 

TwUt 

Delta MeUl: 

Torsional strength. . 

Ebstio limit 

Twist 

>* Manganese Bronse: 

Torsional strength. . 

Elastio limit 

Twist • 



72.400 

41.050 

3 and 152° 

68.990 

42.710 

3and180' 

59.590 

24,530 

7 and \3fJP 

101.200 
57.200 
3 and 140'' 

91.900 

17.250 

9 and W 

104.800 

21.800 

11 and 100° 

91.990 
37.780 

11 and ISO" 

94.610 
45.510 

12 and 150° 

83.840 

42,540 

2 and 280° 

137,295 

54.100 

345° 

51.200 

32.600 

2 and 225° 

61.200 

26.850 

2 and 155° 

70,000 

34.250 

12 and 95* 

61.630 

26.940 

180°. 

61.630 
22.040 
2 and 5° 



82,350 

32,800 

I and 265° 

77.210 
29.430 

1 and 349" 

49.260 

9,830 

3 ind 190° 

82,500 
36.200 

3 and 10° 

64.490 

8.150 

8 and 115° 

78,550 

15.700 

6 and 330° 

78.030 
36,140 

4 and 320° 

83,030 
33,940 . 
5 

76.650 
36.800 

2 and 30° 

124.080 
37.750 

1 and 250° 

43.780 
22,180 

2 and 185° 

36.560 
9,800 

51,020 

21,240 

I and 215° 

42.860 
14.600 

3 and 235° 

37.630 

13.060 

3 and 1 10° 



41,175 

26,350 

i6 

33,680 

25.460 

9 and 1I5« 

33.061 
7.310 
12 and 120° 

19.590 
13.060 

3 and 110° 

41.300 
6.560 
Sand 40° 

53J70 
10,^ 
6 and 195° 

54.210 
19.800 

4 and 90° 

72,290 

31,300 

9 and 205* 

15,920 

2.040 

8and 230P 

67.710 

17,820 

320° 

14.190 
4,100 

5 and 40° 

8.860 
1,630 

3 and 255° 

19.920 

6.560 

15 and 200° 

3.265 
1.360 

4 and 300° 

8.980 
3.260 
2 and 10° 



12.350 

6.550 

8 and 132° 

17,250 

9,034 

12 

26,530 
2,450 
61 and 260° 

14,340 
6,560 
8 and 35** 



6.560 

8 and 132° 

25.350 
6.040 

9 and 210° 

38,600 

10.680 

land 50° 

40.610 

10.910 

6 and 240* 

7.180 
1.630 
39 and 199° 



72 



NON-FERROUS METALS AND ALLOYS 



Tftble 19. Phyiioftl Propertiei of Boarinf Metalt 



Kind of 
mateiiM 



Composition in per cent 



& 
§• 



1 



a 



o 
B 

I 



« 

M 



o 
a 



Tensile test 












Is 

d d 

I* 



If 



BiineU 
test 



fiOO-kg. 
load, 10- 
mm. ball 



Hard- 
ness 
number 



c( 

IS 

55 



s 

o 

o 



Coqip: 
sion test 



Original 
section 



LS 



8 

I 



Phosphor |79 
bronse. 



Cypnis bronBe.|64 
Plastic bronse. 64 
Demo bronse. 60 
Plu mbi 50 

bronae. 
Standard 

Babbitt. 
German Bab- 
bitt. 
Souther Bab- 
bitt. 
Parsons white 

brass. 
S h o n berg 
M. metal. 



.701 

75 
.00 

.a 

.00 
.70 
.55 

.00 
.25 
.50 



9.50 

30.00 
30.00 
32.97 
50.00 



0.15 
0.25 



10.00 

5.00 
5.00 
4.60 



88.89 
88.33 
84.00 
64.90 
58.38 



1.0 

12.1 



7.41 

11.11 

9.00 



32.93 
38.93 



23,920 

17,380 
21,340 
18,170 



11,780 
8,726 
10.000 
21,416 
11,710 



2.875 in 8* 

6.5 in 8' 
10.10 
3.00 



5.00 



1.25 

11.25 

4.00 



8.20 
0.35 



3.14 



18.72 
5.76 



55.00 

41.25 
45.00 
52.00 
21.80 

27.70 

21.10 

34. 

18.00 

25.10 



53.0 
59.0 



80 48 



29.0 
22.5 

19.0 
31.5 



•••«•• 



64,490 
56.220 



29.150 
33.895 
28.410 
75.460 
36,755 



44.2 
30.4 



59.0 
59.2 
44.1 
73.8 
54.8 



Copper-base Bearinir Metals 
The oopper^base alloys (usually known as bronses) consist of the follow- 
ing classes: 1. Copper and tin. 2. Copper, tin and sine. 3. Copper, tin 
and lead. 4. Copper, tin, lead and sine. Occasionally there are added 
small proportions of other metals, which modify the general properties of the 
allojrs. 

Copper-Tin Bearing Alloys. About 30 years ago these alloys were in 
popular use, not only for machinery bearings but also for car and locomotive 
bearings, the alloy of 7 copper and 1 tin being the one most commonly used. 
This alloy has a high compressive strength, is quite hard and should be used 
only in cases where heavy pressures are encountered. Their use in other 
bes^ngs is not justifiable, because the alloys have very little plasticity and 
therefore become heated upon little provocation, and have a high rate of 
wear. 

Bell metal is a still harder metal than the 7-to-l bronae, and carries from 16 to 26 
per cent of tin, the balance being copper. Such bearings have been tried because of 
the false idea that the harder metals will better resist wear. Their use has alwaya 
met with failure. 

Copper-Tin-Snc Bearing Alloys. The addition of sine to the copper- 
tin alloys improves their casting qualities. Such alloys are very rarely used 
to-day. except for backing a softer lining metal. The housings or backs on 
marine bearings are usually of this alloy. It is used by the United States 
Government and to some extent in the automobile trade, the bearings usually 
being lined with a high-tin-base Babbitt metal. This is a very expensive 
form of bearing and its use in many cases is not justified, as more satisfactory 
service could be rendered by cheaper alloys. 



BBARINO MBTALS^BBOIfZBS 73 

Ooi»p«r*Tia-Leftd BMcinir Allojni. This class of alloys is the standard 
bionse alloy in use to-day for bearings. The standard phosphor-bronse 
bearing metal is an alloy of these three metals containing a small percentage 
of phosphorus. It was found about 25 years ago that the addition of lead to 
the then standard copper-tin alloy made the alloy more plastic and therefore 
better able to conform to inegularitiee of the service without heating, and 
diminished the rate of wear. 

Dr. C. B. Dudley as a result of many investigations found that the rate 
of wear in a bearing metal and its tendency to become heated in service 
Hiiwinimh with the iucrease of lead and with the diminution of tin in the alloy. 

The following wries of alloys were experimented upon by the Pennaylvania Railroad 
under the direction by Dr. Dudley: 

Percentage composition 
MsTAi* Tbbtbd Relative 

Copper Tin Lead Phosphorus Arsenic wear 

Phosphor bronse, standard. 79.70 10.00 0.60 0.80 1.00 

Ordinary bronse 87.50 12.50 1.49 

Anenie bronse, "A" 80.20 10.00 0.80 1.42 

Arsenic bronse. "B'* 82.20 10.00 7.00 0.80 1.15 

Arwnie bronse. *'C" 79.70 10.00 9.50 0.80 1.01 

^ „. ..«.„ / 77.00 10.50 12.50 0.92 

"~"^' * 1 77.00 8.00 16.00 0.86 

An ftlloy of M p«r e«nt eopp«r, 10 per cent tin, and • p«r cent lead 

will withstand oompjession of approximately 24,000 lb. on a Uin. cube at the 
yield point; a 1-in. cube will compress 26 per cent under a load of 100.000 
lb. without fracture. The compressive strength is sufficiently high for .it to 
be used in severe service; it is an admirable alloy for connecting-rod brasses. 

An alloy off 80 par cant ooppar, 10 par aant tin, and 10 per cant lead, 

as compared with the alloy canying but 5 per cent of lead, shows a diminished 
resistance to compression, namely, 23,000.1b. en. a 1-in. cube at the yield 
point, and a compresaon under 100,000 lb. of 29 i>er cent. This alloy is 
very largely naed for locomotlva, car, and general nubohinary bearings. 
A small percentage ol phosphorus is often added and the alloy is thep known as 
standard phosphoi^bronze bearing metal. (S. A. E. Specification No. 26— 
0.05 to 0.25 per cent P.) The phosphorus adds somewhat to the resistance 
to compression and to the fluidity of the metal, but it has not been proved 
that it benefits in any way the quality of the alloy from the standpoint of 
service as a bearing. In fact, the limited data at hand tend to show that it 
acts adversely in service, because of the production of the brittle phosphide 
of copper in the alloy wldch frequently tends to cause heating. This alloy, 
nevertheless, is called for in the specifications of many prominent consumers. 

The alloy of 77 par cant copper, 8 per cent tin, and 16 per cent lead 
is extensively used, and together with a small percentage of phosphorus (0.2 
per cent) is known on the Pennsylvania Railroad as Ex. B. metal. This is 
the alloy of highest lead and lowest tin oontent which Dr. Dudley was able 
to produce, owing to foundry difficulties. Alloys of lower tin and higher lead 
segregated, the lead liquating to the bottom of the casting, due probably to 
the presence of phosphorus which lowers the solidifying point of the alloy and 
therefore maintains the alloy in a liquid condition for a longer period. This 
alloy win support a load of 21,000 lb. on a 1-in. cube without distortion. 
It has a slow rate of wear and is less liable to heat in service than either of 
the two preceding alloys. 



74 



NON-FERROUS METALS AND ALLOYS 



Copper, 


Tin, 


Lead. 


Wear. 


per cent 


per cent 


per cent 


in grams 


81.27 


6.17 


14.14 


0.0327 


76? 


57 


20? 


0.0277 


68.71 


5.24 


26.67 


0.0204 


64.34 


4.70 


31.32 


0.0130 



Alloys oontaining from 4 to 7 per cent of tin, and 20 to SOper oentofiead, 
are known in the trade as AJax plastic bronae allosrs. and are manufactured 
l^ the Ajaz Metal Co. The patent controlling these alloys is based upon the 
fact that lead which is only mechanically held in the alloy can be prevented 
from liquating to the bottom of the casting if the copper and tin matrix which 
holds it can be made to eoUdify quickly. Quick solidification of the matrix 
will result if the copper and tin arc in correct proportions, that is, in such 
proportions that only a solid solution of the two metals is formed. The fol- 
lowing table gives the results of tests made in the author's laboratory. 

Copper, Tin, Lead, Wear, in 

per cent per cent per cent grams 

86.76 14.90 0.2800 

90.67 9,45 0.1768 

96.01 4.95 0.0776 

90.82 4.62 4.82 0.0542 

85.12 4.64 10.65 0.0380 

It was found that the addition of a smaU percentage of nickel adds to the 
compressive strength of the above series of alloys, and also elevates the tem- 
perature of solidification of the matrix. Ajax plastic bronzes of various grades,^ 
having compositions within the limits above set forth and also with the addi- 
tion of 1 per cent nickel are in use very extensively for locomotive and oar 
bearings, cold-roll neck mill bearings, etc. 

Parsons Bronse. An excellent metal for the thrust blocks of Mitchell 
and Kingsbury Thrust Bearings is Parsons Bronse. Its percentage com- 
position is copper, 80.75 to 84.75; tin, 12.8 to 14.8; lead, 2.45 to 4.45; material 
not specified (impurities),' not to exceed 1. Where high pressures are en- 
countered and sudden burning out of a bearing may endanger the turbine 
blading it is advisable to use this hard metal. The lubrioation must be of 
the forced type. 

Copper-Tin-Lead-Zinc Bearing Alloys are the cheapeet form of bronse 
bearing-metal alloys on the market. Zinc is an adulterant which usually 
enters the alloy through the use of miscellaneous scrap. The following 
tests made in the author's laboratory show the efiFect on the rate of wear of 
increasing amounts of zinc. 



Copper 


Tin 


Lead 


Zino 


Wear, in grama 


86.12 


4.64 
5.28 


10.64 
10.25 




0.0380 


82.27 


2.07 


0.0415 


79.84 


4.71 


10.30 


5.44 


0.0466 


77.38 


5.62 


11.42 


6.54 


0.0672 


74.28 


4.68 


10.61 


11.04 


0.0848 



Zinc adds to the brittleness of the alloys, and this probably accounts for 
the more rapid rate of wear due to cine content. The canying of considerable 
zinc in the presence of fairly high percentages oC lead has the further detri- 
mental effect of causing the alloys to become somewhat weakened under the 
influence of elevated temperatures. The best bearing bronzes do not contain, 
zinc, and its presence is restricted to below 1 per cent in the specifications 
of the most prominent consumers. The Society of Automobile Engineers 
specification (No. 27) for red brass is copper, 85; tin, lead and zinc, eaolk 
5 per cent. This is said to machine well and to be an excellent bearing metal, 
where speed and pressure are not excessive. 



BSAR2N0 METALS—BABBITTS 75 

Tin-b«M Baarinc Ifotalt 

Tm-base bearing metals (tin over 50 per cent) oome within the classifi- 
cation oommonly known as Babbitt motaia, and are divided into three 
dasaee: 1. Tin, antimony and copper alloys. 2. Tin, antimony, copper 
and lead alloys. 3. Tin, copper and zinc alloys. They possess in general a 
higher resistance to compression than the lead-base metals. The resistance 
to compression* however, is due in a very large measure to the relative per- 
centages of copper and antimony which the alloys contain. Copper and anti- 
mony are the hardening constituents in such alloys, and, although they may 
also contain a certain percentage of lead and infrequently small percentages of 
other metals, the eesential properties are derived from these two metals. 

The name "Babbitt" is derived from that cf the inventor (Isaac Babbitt) 
of soft-metal-lined bearings. The term ** babbitting'* has been applied to the 
process of applsdng soft anti-friction metals inside of a harder shell for the 
purpose of producing bearings. The beet-known soft-metal alloy at the time 
of the invention was the high-grade pawtar alloy then used, the composi- 
tion of which was copper, 3.70 per cent; antimony, 7.40 per cent, and tin, 
8&90 per cent. This particular alloy became known as "Genuine Babbitt," 
although the tarm is now more generally applied and includes all tiiv-anti* 
mony-copper alloys in which tin is the base metal, and which do not oootain 
lead or linc. 

Soft Oanuina Babbitt is usually made to the formula above given for 
Isaac Babbitt's original metal. Sometimes, however, this composition is 
■lightly varied between 91 per cent tin, 4H per cent lead, and 4H por cent 
antimony, and 88 per cent tin, 4 per cent copper and 8 per cent antimony. 
The latter compodUon, as quoted by Charpy on a test piece 0.6 in. in height 
and 0.0155 sq. inu in sectional area, under a load of 1929 lb. showed a compres- 
Bon of 0.008 in^ and under a load of 4960 lb. showed a compression corre- 
sponding to 0.3 m. This metal is free-flowing, tough, and gives excellent 
service in bearings where the loads are not heavy. 

U. S. VaTj SpMlfleationa (Adopted, iUT) for Antl-frietlon Metal oalla for the 
folloiring p^ceniage obemioal composition: Tin, 88 to 89.5; antimoDy, 6 to 8; oopper, 
3 to 4.5. 

Marine Use. This metal is suitable for white metal liner bearings, and bearing 
surf sees. 

The Society of Automobile Engineers Specification for Babbitt Metal 
No. 1 is: tin, 89 per cent; antimony, 7 per cent, and copper, 4 per cent. 
A variation of 2 per cent either way is pwmissible in the tin content, and a 
variation of 1 per cent either way in the antimony and copper. Only traces 
of other metals are permissible. 

Hard Oanuina Babbitt. The composition of this alloy may range from 
83 per cent tin, 8){ per cent antimony, 8^ per cent copper, to 80 per cent 
tin, 10 per cent antimony and 10 per cent copper. For the former Charpy 
gives the following figures: A test piece 0.6 in. in height and 0.0155 sq. in. 
in sectional area, under a load of 2646 lb., gave a compression of 0.008 in., and 
imder a load of 5622 lb. a compression of 0.3 in. The metal of the latter 
formula would sustain a higher load with equal compression. 

The method of casting and rate of cooling have a very important influence 
upon the structure and service which these metals will give. The rate of cool- 
ing affects the hardness of the matrix, and the size and number of the tin- 
antimony crystals. The proper temperature for pouring is approximately 
810 deg. fahr., and the metal should preferably be cast against a chill heated 



76 NON'FERROVS MBTALS AND ALLOYS 

to a temperature of approximately 212 deg. fahr., 86 that the rate of oooH&g 
is not too rapid. 

The specification of the Society of Automobile Engineers for Babbitt 
Metal No. 2 is: tin. S4 per cent; antimony, 9 per cent; copper, 7 per cent. 
A variation of 2 per cent either way is permiasible in the tin, and a varia- 
tion of 1 i)er cent either way in the antimony and copper; only traoea of 
other meteds. Specifications Noe. 1 and 2, above given, are also used in 
making die-caat boarlngB. An alloy of 80 tin, 10 copper and 10 antimony 
ii. used on the high-speed bearings of De Laval turbines. 

Tin-base Babbitts Containing Lead. Lead has the property of increas- 
ing the fusibility of the tin-base alloys by forming a eu tec tic of low melting 
point, but the tin present should preferably be over 50 per cent, the antimony 
not less than 12 per cent, and the copper not less than 3 per cent for the best 
results. The alloys may be made within a wide variation of composition, the 
hardness depending on the increasing percentages of copper and antimony. 

Tin-ba4M Babbitts Containinff Zinc. The most important alloy of 
this class is (Parsons') white brass, which consists, approximately, of 62 per 
cent tin, 35 per cent sine, and 3 per cent copper. (S. A. E. Specification: 
Cu, 3 to 6; Sn > 65; Zn, 28 to 30.) It is largely used for marine bearings 
and to some extent for automobile bearings. Such bearings should be 
well lubricated. It is hard, tough, is rather sluggish to pour, and cannot 
for this reason be oast into thin sections after the manner of using Uie ordinary 
Babbitt metals. It must be poured at a fairly Jiigh temperature, approaching 
redness, and is preferably peined after casting to compress the metal and so 
add to its durability under the influenoe of wear. 

Lead-base Bearing Metali (Babbitts) 
Lead-base bearing metals Gead over 50 per cent ) are divided into three 
classes: (1) Lead-antimony alloys; (2) iead-antimony-tin alloys; (3) lead- 
antimony-tan-copper alloys. The useful alloys of lead and antimony for bear- 
ings contain from 7 to 20 per cent of antimony. . Below 7 per cent the cdloys 
are too soft, and above 20 per cent too brittle, for practical uses. Lead and 
antimony are insoluble in each other in the cold, and the solidified alloys there- 
fore consist of lead and eutectic alloy if antimony is present below 12.8 per 
cent , and of antimony and eutectic alloy if antimony is present in excess ol 
12.8 per cent. This is the cheapest class of anti-friction metal which can 
be produced, as lead sells at the lowest price of any of the metals, and antimony 
usually sells at only two or three times the price of lead. The alloy commer- 
cially known as Ho. 4 Babbitt consists of 88 to 90 per cent of lead and 10 to 12 
per cent of antimony. Magnolia metal is a lead-tin-antimony aUoy, 
together with traces of copper, sine, iron and possibly bismuth. A reoent 
analysis shows lead 70, tin 5, antimony 16% 

Charpy haa determined the compreaeive strength of several of these alloys and his 
results are given in iLe following table (test pieces as given under "Soft Genuine 
Babbitt"): 

/M ... . I, Load corresponding to Load cerrespondlng^ 

CompodtiMi of aUoy. a permanent set to a permanent set Remarks 

P~<»^* of 0.008 in., of 0.3 in.. 
Lead Antimony lb* lb. 
100 0.0 220 1100 
go 10 1433 2866 
82.5 17.5 1433 3197 Broke at 

80 20 1676 2766 lb. 

Lead-Tin-Antimony Allojn are very largely in use as Babbitt metals 
beoause of their low price, and because they perform very satisfactorily if 



BEARINO MSTALS^BABBITTS 



77 



und in the proper eervioe and under the proper oonditionB. Many of the 
videiy advertiaed brands of Babbitt metal oome within this class. 

Charpy stotM that the alloys of lead, tin and antimony are eimilar to those of 
lead and antimony; but the addition of tin diminishes the hardness and britUeness of the 
hard grains and also increases the compressive strength of the eutectic alloy. For this 
reason the alloys of lead, tin and antimony are superior to those of lead and antimony 
alone. He states that the tin must be present to the extent of more than 10 per eent . 
hot not necessarily more than 20 per cent , and the antimony may vary between 10 and 
18 per cent. The following table compiled by him shows the compressive strength of 
this ssries of alloys, test pieces as given under "Soft Genuine Babbitt,*' p. 76. 



Composition 


Load corresponding to 
a compression of 


Composition 


Load corresponding to 
a compression of 


Lead Hn 


0.008 in. 


O.SIn. 


Lead 


Tin 


Antimony 


0.008 in. 


0.3 in. 


40 
(A 

n 


100 
00 
60 
40 
20 


661 
1323 
1433 
1323 
1047 


2333L 

3858 

3252 

3066 

2535 


10 
20 
40 
60 
80 


80 
60 
40 
20 
10 


10 
20 
20 
20 

10 


2425 
2976 
2535 
2315 
1764 


5952 
4850 
4023 
3748 
3913 



Load-Antiinoiij-lPiii-Copper Alloys. The addition of oopper to the 
alloy of lead, tin and antimony increases the hardness and causes an increased 
aluggishneos in pouring, depending on the ' amount of copper present in 
proportion to the tin. 

In the high-tin-carrying alloys the percentage of copper can be increased 
without increasing the sluggishness. With 10 per cent of tin, not over H 
per cent of copper should be added; with 20 per cent of tin, not over 1 per 
cent ; with 30 per cent of tin, not over 1V6 per cent' ; with 40 per cent of tin, 
not over 2 per cent , and with 50 per cent of tin, not over 3 per cent copper. 
A great many Babbitt metals are on the market having these four con- 
stituent metals in their composition, which are known in the trade as "cop- 
per-hardened Babbitt," and are designated by grades according to the amount 
of tin which they contain. 



2inc-base Bearing Metals 

Lmnon Metal oonaiBts of 85 per cent sine, 10 per cent oopper, and 5 
per cent aluminum. This alloy has a low coefficient of frietion, a low 
specific gravity, and is capable of being cast in sand after the manner of brass 
and bronse castings. It is easily machined, and because of its low' price 
and low specific gravity has found considerable favor in certain classes of 
service such as motor bearings, crane bearings, etc. It should be used, however, 
in bearings which can be maintained in fairly good adjustment, because, 
owing to the high sine content of the alloy, it becomes brittle under the 
effects of hcMiting, and in the absence of an oil film is quite liable to grip the 
journal. It is an excellent metal for high-speed bearings carrying little 
weight. Fenton's all<^ eontaina 10 per cent tin, 5 per cent copper, and 70 
per cent ainc. 

Alloys for Die Castin^r* Castings in which the molten metal is forced 
under pressure into accurately cut metal dies are now largely used in the place 
of small sand castings formerly made of brass and machined to sise. It is 
possible in this way to produce parts of more or less intricate shape that are 
veiy accurate in sise and smoothly finished. Babbitt metals are used in 



78 NON-FERROUS hiETALS AND ALLOYS 

makiiMS die-cast bearings, while other maohine parts are made from xino- 
base alloys, the two most extensively used having the following oompositions: 

I II 

Zinc 89.00 82.00 

Aluminum 0.25 0.25 

Tin 7.00 14.50 

Copper 3.25 3.25 

These and similar lino alloys have a tensile strength not ezoeeding 18,000 lb. per sq. in., 
and an exceedingly low elongation and reduction of area. They compare favorably in 
strength with cast iron. They are corroded by aqueous solutions and should not be used 
for food containers or conveyors. Commercial gasoline when in direct and eonstant 
contact will also corrode them; copper plating, however, will aid in resisting its 
attack. 

BUioellaoeoug WhiU-motal Alloyi 

Alloys for Metallic Packixig. For casting metallic packing rings the 
following inexpensive alloy has been found to give the best results: Lead, 
83 H per cent; tin, 8H per oent; antimony, 8H per cent. Metallic 
packing for use with superheated steam should not fuse under the temperature 
produced by the combined effect of the temperature of the steam and the 
friction on the rod, should have sufficient plasticity to produce a tight joint, 
and should show but a slight amount of wear. A composition fulfilling these 
requirements, when only a smaH amount of superheat is used, consists of 80 
per cent lead and 20 per cent antimony. 

Fugible Alloys. By the addition of varjang percentages of bismuth 
or cadimum to lead«tin alloys of different oompositions, the melting points 
may be greatly lowered. Such alloys expand on cooling and are little used 
for marine work. Some of these compositions (parts by weight), together 
with their melting poinU are as follows: 

Alloy Tin Lead Bismuth Cadmium uoint 

deg. fahr. 

Lipowitc's 4 8 15 3 140 

Wood's, 4 8 15 4 168 

Darcet's 25 25 50 203 

Cliche metal 2 2 5 221 

Rose's 24.6 28.1 50 230 

Bismuth solder 24.8 22.1 53.1 250 

Solders and Braiing Metals. Soft solders are used for joining tin 
plate and other metal sheets. A 90-tin-lO-lead solder melts at 410 deg. fahr., 
and a 7O-tin-30-lead alloy at 384 deg. fahr. Plumber's solder oonaists of 2 
parts lead and 1 part tin. Brasing solder, or brasing spelter, as it is oom«- 
merdally termed, consists of 50 to 55 per cent of sine, the remainder beins 
copper. This is cast in ingots and granulated under a drop hammer into 
grades known as "long grain," "short grain," "fine grain," etc. The alloy 
mainly used as brasiiiig metal consists of 80 per oent copper and 20 per oent 
line. Brasing solder and metal are used to unite brass, copper, iron and 
steel in strong joints'. 

U. 8. Marr Bpeelftoations (Adoiited.'lf IT) for Spelter Solder designate two grades: 
Longrgrain spelter solder which consists of not less than 52 per cent oopper, not 
more than 0.2 per cent lead, not more than 0.1 per oent iron, and the remainder sine; 
Orey spelter solder which consists of 40 to 52 per cent copper, 3 to 3.5 per cent tin, 
not more than 0.5 per cent lead, and the remainder sine. 

Vluzes for soft solders, powdered rosin, hydrochloric acid "killed*' by the additioa 
of line scraps, and tallow (by plummers). Sal ammoniac is sometimes used in brasing 
eopper. 



IRON AND STEEL 

BY 

D. J. McADAM, JR. 



RarBBVcn: Hsrbord and Hall. "The Metallurgy of Steel/' Griffin 4b Co. Bradley 
Steogbton. "The Metallurgy of Iron and Steel." McGraw-Hill Book Co. Campbell. 
"The Manufacture and Properties of Iron and Steel." MeGraw-Hill Book Co. Becker, 
"Higb Speed Steel," McGraw-Hill Book Co. Hall. "The Steel Foundry." MoGraw- 
Mill Book Co. Howe. * 'Metallography of Steel and Cast Iron." McGraw-Hill Book Co. 
JohiMon, "Blast Fumaee Operation and Construction in America," McGraw-Hill Book 
Co. MoMenke, "Prinoiplee of Iron Founding." McGraw-Hill Book Co. Giolitti, 
"Cementation of Iron and Steel," MoQraw-Htll Book Co. Sauveur. "Metallography 
•ad Heat Treatment of Iron and Steel," Sauveur and Boylston. Hatfield, "Caet 
Iron in the Light of Recent Research," Griffin A Co. Foreythe, ' 'Blast Furnace and 
the Manufacture of Pig Iron," David Williams Co. 

ORS8 or IRON 

Ck>mpoiition. Commercial ores of iron consist of compounds, usually 
oxides, mixed with various non-ferrous minerals known as "gangue.** The 
most important oommercial ores of the United States are hematite, Umonite 
and magnetite. 

Hematite. More than three-fourths of the iron ore mined in the United 
States consists of hematite, FesOs, which is identical in composition with red 
iron rust. This mineral when pure contains about 70 per cent iron. It is 
either deep red or black in color and gives a red streak when rubbed on un- 
glased porcelain. The red varieties vary from compact, columnar or botry- 
oidal masses to loose earthy material. Black hematite occurs in brilliant scaly 
msflses known as specular iron ore. 

Uiaonit*, FetOr nHiO, is essentially a hydrated hematite and is some- 
times called brown hematite. When pure it contains about 60 per cent iron. 
It varies in color from yellow to dark brown and may be soft and pulverulent 
or hard and compact, but is never crystalline. It gives a yellow streak on 
QQglased porcelain. 

Kafnetite, FeiOi, is a heavy hard, black mineral frequently occurring in 
octahedral ciystals. It gives a black streak on unglazed porcelain. When 
pan h oontaina a higher percentage of iron than any other mineral. In 
the United States, it frequently occurs mixed with non-ferrous elements that 
make its extraction difficult or that make the ore unsuitable for use in steel 
m>1r^T|g without previous concentration. In Sweden, however, this ore occurs 
in a high decree of purity. 

Siderlte, FeCOs, though rarely \ised as an ore in the United States, is used 
in certain districts of Europe, especially in the Cleveland district of England. 
It occurs as rhombohedral crystals which when pure contain only 48.3 per 
cent of iron. Before use it is always calcined to remove the carbon dioxide. 

Location of Ores In the United States. Immense deposits of hematite in the Lake 
Bupefwrdiatriot furnish more than ^ of the iron ore mined in the United States. Brown 
hematite or liiaonite. toftether with red hematite, occurs in the Appalachian region from 
New York to Alabama, and is mined throughout this region, but especially in Alabama. 
linonite is ako mined in Colorado. Magnetite ores are mined in eastern Now York, 
aorthem New Jersey, Pennsylvania and Colorado. 

79 



80 IRON AND 8TBSL 

The VftliM of an Iron On depends on the pereentace of iron that it eontaina. The 
greater part of the iron ores mined in the United Statee oontain from 50 to 60 per pent 
of iron and are used without previous concentration. When an ore contains leas than 
40 per cent of iron, however, it must be concentrated cither by washing or by magnetic 
separation. In some cases also the ores must be prepared by calcination, roasting or 
agglomeration. 

The value of an ore depends also on the eharaoter of the f angue and the quantity 
of certain elements that it contains. Of all the elements occurring in the gangue phoa- 
phorui and sulphlir are the most objectionable. The phosphorus usually occurs as 
ealeium phosphate and the sulphur as iron pyrites. Unless the sulphur percentage in the 
ore b unosuidly high the percentage in the iron obtained wiU not be excessive sinoo 
about ^Me of the sulphur in the ore and fuel is removed in the smelting process. Prac- 
tically all the phosphorus in -the ore, however, will be found in the iron after smelting. 

The percentage of phosphorus is the basis of the classification of all iron ores as either 
B eMo i D T or non-Baasaniar according as they can or cannot be used in the Bessemer 
process of steel making. If an ore contains more than 0.001 as much phosphonas as iron, 
it cannot be used in the Bessemer process and is therefore called a non-Beesemer ore. 
Within each of these two great olasses, there are further subdivisione also based on tlio 
phosphorus content of the ore. 



EXTRACTION OF IRON FROM ORE 

Proceflses of making wrought iron and stcol directly from the ore date back 
to prehistoric times. Such processes are now practically obsolete. Thoy 
have been unable to compete with the blastfurnace process, which produces 
pig iron, from which all other iron products are made. 

^ Ths Blast Furnace. This is a vertical shaft furnace, 80 to 100 feet in height and 
circular in section. Successive layers of fuel, ore and flux are continually charged into 
the top of this furnace and liquid iron and slag are withdrawn at intervals at the bottom. 
The fuel is burned by a blast of preheated air which enters at the bottom of the shaft. 
There is thus a continuous, slow downward movement of the solid charge and a continu- 
ous, upward rush of heated gases. The combustible gases leaving the top of the 
shaft are utilised to preheat the air blast and to furnish power for auxiliary machinery. 
In addition to the furnace with its hoists for handling the charges and its ladles for 
handling the liquid products, other essential parts of the equipment are blowing engines, 
hot blast stoves and water pumps for cooling coils. 

At the bottom of the shaft is the crucible or hearth about 17 feet in diameter and 
about 8 feet in height. Above the hearth the shaft widens out gradually through a 
vertical distance of 14 feet, until the diameter is about 22 feet forming what is called the 
"boih." Above the bosh the walls converge until a diameter of 17 feet is reached again 
near the top of the shaft. The blast enters through a series of 10 to 15 circular openings 
called "tajSTM," situated near the top of the hearth and arranged at regular intervals 
around the circumference. 

The fuel in most general use is coke, though a few furnaces use charcoal or anthracito 
coal. The flux, usually limestone, is added for the purpose of forming a fuidble slag 
with the gangue of the ore and the ash of the fuel. In the hot blast, the fuel burns to 
carbon monoxide and this gas mixed with the oxygen of the air ascend^ through the shaft. 

The process of iron smelting in the blast furnace consists of two distinct stages. 
In the shaft above the bosh the reduction of iron oxide to solid spongy metallic iron is 
gradually accomplished, chiefly by the chemical action of the carbon monoxide. By the 
time the descending charge has reached the upper part of the bosh, the reduction of the 
iron is practically complete, and the lime and the gangue have united to form a viscous 
slag. 

At the top of the bosh, the iron melts and together with the slag trickles over the burn^ 
ing fuel which is the only remaining solid. The iron rapidly absorbs carbon and other 
constituents at this stage and falls into the hearth as molten cast iron. The slag floats 
on the top of the molten iron and is drawn off through the slag hole. The iron is then 



BLAST FURNACE PRODUCTS 81 

diBwn off through a hole at th« bottom lerel of the hearth and either east |&tO ** pics" 
or ond IB the molten ooncfition for one of the steel making proo ooBOB . 

The productive capacity of a modern blaet furnace ia about 600 to 560 tone per day. 
For each ton of iron produced there are required about 2 tone of ore, H ton of flux, 
I ton of fuel and about 4 tons of air. For each ton of iron, there are produced about 
5H tons of waste gases and H ton of slag. 

Blait 7umace Products 

Control of Oomposition. Regulation of the proportions of the various 
materials of the charge is not only necessary for the successful operation of 
the furnace, but also is the chief means for control of chemical compo- 
aUon of the products. As stated above, the percentage of phosphorus in 
Uio pig iron cannot be controlled by the blast furnace operation, but depends 
entirely on the quantity of phosphorus in the charge. Of all the elements 
whose percentage can be controlled by the blast furnace process, silicon and 
sulphur are the most important in their effect on the quality of the iron. 

Silicon. For the control of lUicon, the chief factors are hearth tempera- 
ture and slag composition. At the high temperature of the hearth, silica 
is reduced by the solid carbon of the fuel and the silicon is absorbed by the 
iron. The higher the temperature, the larger the proportion of silicon formed. 
On the other hand, the greater the ratio of lime and magnesia to the silica in 
the slag, the less silica is reduced to silicon. By varying the proportions of 
fuel and flux in the charge, therefore, the hearth temperature and the slag 
composition can be varied so as to regulate the percentage of silicon in the 
iron within certain limits. The upper limit which is about 6 per cent in 
pig iron, depends on considerations of fuel economy, since the required heat 
energy increases rapidly with increase in the percentage of silicon. It is 
extremdy difficult to make iron with less than 0.2 per cent in the coke furnace 
without a consequent objectionable decrease in the i)ercentage of sulphur. 
In the charcoal furnace iron can be produced with silicon as low as 0.1 per cent. 

Sulphur is the element that indirectly produces most of the dilRculties 
in the operation of the blast furnace. The maximum allowable percentage 
of this element in the iron is usually not above 0.04 or 0.05. Since coke 
usually contains at least 1 per cent of sulphur, and since about a ton of fuel 
m required for each ton of iron produced, evidently about ^He o' the sulphiur 
in the charge must be kept out of the iron in the operation of the coke fired 
blast furnace. Since sulphur is carried in the slag as calcium sulphide and in 
the iron as iron sulphide, the proportion kept out of the iron can be increased 
fay increaaing the basicity and volume of the slag. The absorption of sul- 
phur by the slag is also facilitated by increasing the fluidity and temperature 
of the das- Since some of the factors may conflict, a proper balance of all 
these faetoTB wiU produce the best results. 

In general, high silicon in the iron tends to be accompanied by low sulphur 
and vice vena. It is difficult to obtain iron low in both silicon and sulphur 
from the coke fired blast furnace. Since the charcoal fired furnace has the 
advantage of use of a fuel almost free from sulphur, such furnaces can 
produce iron low in both silicon and sulphur. 

The pereontaffe of cwrbon in pig iron rarely rises above 4.3 or falls below 
3.5. In iron from the cold blast charcoal furnace, however, the percentage 
may fall as low as 3.0. High hearth temperature or high percentage of man- 
ganese tends to increase while high percentage of silicon tends to decrease the 
ibsorpUon of carbon by the iron. 
6 



82 



IRON AND 8TEBL 



BlanganeM cannot be bo readily oontroUed as can acme of the other ele- 
ments. OnHnarily from H (<> ^ of the maganeee in the charge goes into tho 
iron. High temperature and basic slag favor the release of manganese from 
the slag and its absorption by the iron. On account of the affinity of man- 
ganese for sulphur and oxygen, it is desirable to have 0.50 to 0.75 per cent of 
manganese in pig iron. 

OhuMifloation of Blast Furnace Produeto Aeeordlxig to Uses. From 
the products of the blast furnace originate all these countless objects of iron 
or steel so essential to our civilisation. These products in the order of their 
importance may be divided into the following groups: steel-making irons, 
foundry irons, puddling irons and ferro-alloys. The second group includes 
all these irons which are to be used without further change except remeltlng, 
the other three groups include the pig-iron and ferro-alloys that are to be sub- 
jected to other metallurgical processes. 



SkftlctMi of Amorleaa Ir<m Jfc Stoel Mura^ctore 



W.4IIMr4fletXmtf(M 




Ov.TaH«inilnB 






hE 



1.0lftJ»T« 



•I.WI.M8 V«t TWm «f Ook« 



fludCMt 

MmUmCMI 

in 




E.Mf. 



rut«i 



31 



r«m 

Sfk IraM 



£^ 




T^* 



AXLWUtt 



IMOIMOf OfcXaw «( n«l 



nE 




Opw Baith 

H,MT,Mir 

Or Tmt 



PlO. 1. 

Fig. 1, by courtesy of the Secretary, Iron and Sled InstUtUef classifies ail 
blast furnace products according to the various metallurgical processes in 
which they are to be utilised, and gives the approximate percentages utilised 
in each process. The percentages apply to the year 1917, and have doubtless 
been modified' since that date. The duplex and triplex processes are not 
included in the diagram. 



MSTALLOOBAPHT 

The products of the blast furnace, as weU as all iron and steel made fronx 
them, can be classified according to their microstructures as interpreted by the 
science of metallography. Metallography or physical metallurgy, comprises 
the study of the microstructiu'es of metals Id relation to chemical composition, 
processes of manufacture, and physical properties. In the light of this 
science will be discussed as- far as possible all the blas< furnace products, thie 
metallurgical processes to which they are subjected, and the iron and st-eel 



METALLOGRAPHY 83 

thus produced. It will be neoeasaryt however, first to describe briefly the 
types oi niiorQ6tmcture observed in nfetals and alloys. 

Examination of the polished and etched surface of a metal or alloy usually 
reveals one or more of the following types of micro-oonstituents: Grains 
of pure metal, solid solutions, definite compounds, eutectios, nonrmetalUc 
indusbns. The microstructures of all slowly cooled metals are made up of 
one or more of such constituents. 

Pun itf^t^ip The microstnicture of a pure metal consists of grains 
of irregular shape appearing in section as irregular polygons with narrow dark 
lines as boundaries. Each grain is a crystal with definite orientation of axes 
and planes of symmetiy. The boundaries of a grain, however, depend not 
on crystal symmetry, but on limitation of space due to surrounding grains. 
Since the orientation of each grain differs from that of the surrounding grains 
there are variations in the degree of attack of the etching liquid and conse- 
quently of the degree of shading this produced. 

Solid SolutionB. Many metals are more or less soluble in each other in 
the solid state. Some metals are mutually soluble in the solid state in all pro- 
portions. When such an alloy as cast is examined microscopically, it shows 
irregular grains similar to those of a pure metal except that each grain hsa 
a core of a dendritic or pine tree structure. Each core represents a ciystallite 
that formed in the molten liquid constituting a nucleus upon which was de- 
posited layers of gradually changing composition until the grain was complete. 
Throuffhout each grain of alloy as cast, the composition, therefore, varies 
gradually from the dendritic core to the boundary. When such an alloy is 
annealed, diffusion takes place establishing uniformity of composition and 
making the microstructure indistinguishable from that of a pure metal. 

Gompoundg appear under the microscope as crystals bounded by definite 
crystal faces. 

Butactios. When in any alloy the elements are in such proportions that 
it has the lowest melting point of any alloy of the same elements, it is called 
an eutectic alloy. The microstructure of such an alloy consists of alternate 
particles of two or more of the above described micro-constituents. During 
the solidification of the alloy, fine particles of two or more constituents crystal- 
lise simultaneously from the molten mass thus forming a fine duplex or triplex 
structure of characteristic appearance. This characteristic structure, due 
to the simultaneous formation of two or more kinds of crystal, may occur in 
alloys which have not a lower melting point than any other alloy of the 
same elements; nevertheless, all such micro-structures should be designated 
either eutectic or eutectoid structures. 

Hon-metallic InelusioiiB. In addition to the above described essential 
constituents of alloys, non-essential particles are visible in practically all 
metals and alloys. These foreign particles or non-metallic inclusions consist 
of oxides, sulphides, silicates, gas bubbles, etc. 

Phyiieal Properties. Pure metals are relatively soft and ductile, com- 
pounds are hard and brittle, and eutectics and solid solutions have Inter- 
mediate properties. The physical properties of an alloy, therefore, depend 
largely on the types, proportions, and grouping of its. micro-constituents. 

Micro-structures of Iron-carbon Alloys 

The ordinary iron-carbon alloys range in composition from pure iron to 
an alloy containing about 6.7 per cent carbon, and include wrought iron, 
steel, and white and gray cast iron. When classified according to micro- 



u 



IRON AND ST BEL 



Btruetiire, steel and white oast iron fonn a oontinuoua series. Wliite and 
gray cast iron also form a continuous series, which will be considered later. 

Steel- White Oast Iron Seriee. Alloys of this series, after slow cooling, 
consist of only two ultimate micro-constituents in various proportions and 
grouped in various wajrs. One constituent, known as ferrlte, is practically 
pure iron; it is soft (H — 3.6, Moh's), malleable and ductile. The other 
constituent is iron carbide, FetC, known as cementite ; it is hard (H «* 6) 
and brittle. Between the molten condition and room temperatiu«, however, 
a nimiber of transformations take place. All these micro-structures' and their 
inter-relations may be best described with the aid of diagrams such as Figs. 
2 to 5 taken with slight changes from "The MeiaUography of Steel and Coat 
Iron** by Henry M. Howe. 

Iron-carbon Bqullibrium Diagrftm. In the diagram, Kg. 2, the lines 
ABD and A BBC are called respectively the "liquidus" and "toUdui." 






i 



Btml 



1800 

laoo 

1700 

1000 
liW 

IMO 

1400 

1800 

IMO 

IImL Solid j 

ikuitenile or 



Cart lr«ii 

A. 





66 
Solid Eat«ctlc-|- 
Primarf Aastealte 
•t- Pro>«at«ctold 



B 



6C 

Boltd Batacttc-f 

Prinary-fPro>«at«ctoId 

Ccmanllta 



8e 

Pearllta-l-CeiaaatUa 

both Eatectic aad 

Pro-eotactoid 



I 



8d 

Pearlita-fCanaatita 
Primary. Su tactic 
^and Pro-eutectold 



—i {-«.. 

Carbon, Parcent 



1 1 



W 



«.« 



Fio. 2. 

All the area above the liquidus represents liquid aUo3^t the area below t\x^ 
solidus represents solid alloys, and the area between the liquidus and solid t:ia 
represents alloys that are partly liquid and partly solid. The vertical lii^o 
LM represents pure iron and the line DW represents cementite. The lioo 
UV represents an eutectic alloy, containing about 4.3 per cent carbon and 
known as Ledeburite. When a molten alloy of this composition is coole<l 



MBTAUjOORAPBY 85 

Mow the temperatiire repreeenied by the point B, it forms a typical eutectic 
•traeture oomposed of oementite and austenite. Austonito, a solid solution 
of carbon (or iron carbide) in iron, has a range of temperature and composition 
represented by area 4. 

Solid alloys, represented by the diagram to the right of the line RT^ 
contain more or less of the eutectic, while in solid alloys represented by the 
diagram to the left of RT the eutectic is absent. The line RT^ therefore, is 
the boundary between the eutectiferous and non-^utectiferous alloys. It 
represents approximately, also, the boundary between steel and white cast 
iron, though there are some commercial steels having over 2 per cent carbon. 

Molten alloys of the eutectiferous series, on solidifying, deposit first either 
oementite or austenite according as the carbon content is greater or less than 
that of the eutectic. Finally the remaining liquid reaches the composition 
and temperature represented by the point B, when on further cooling the 
eutectac structure is formed. Stypo- or hyper-eutectif eroui alloys, there- 
fore, just below the solidification temperature consist of the eutectic and excess 
of austenite or oementite respectively; the proportion of eutectic decreases 
as the total composition of the alloy departs from that represented by the 
point B. On further cooling, changes take place which will be described after 
first describing the non-eutectiferous series. 

In all alloys represented by the diagram to the left of RT, austenite is formed 
on solidification. Austenite of the composition represented by the line XS, on 
eooling below the temperature represented by the i>oint S, is transformed into 
PMurlite, an "euteetoid" structiuv composed of ferrite and oementite. 
According as the alloy has more or less carbon than the eutectoid composition, 
the austenite on cooling to the lower boundary of area 4 deposits cementite 
or ferrite respectively until the remainder of the austenite is at the tempera- 
ture and composition represented by the point S\ this eutectoid austenite 
00 further cooling is transformed idto pearlite. 

Not only the austenite of the non-eutectiferous series, however, but also the 
austenite of the eutectiferous series, is transformed on cooling from the tem- 
perature of the solidus to room temperature. The alloys represented by 
areas 56 and 5c consist of eutectic and primary austenite or prinuury 
cementite respectively. Both the primary austenite and the austenite of 
the eutectic have the composition represented by the point E when they are 
at the corresponding temperature. On further cooling, however, this austenite 
whether it is primary or part of the eutectic, behaves as does the austenite of 
the non-eiitectiferous series; it deposits cementite until the remaining austen- 
ite is at the composition and temperature represented by the point S, when 
on further cooling the residual austenite is transformed into pearlite. At 
room temperature, therefore, the micro-structures of the eutectiferous series 
are as indicated in areas 8c and 8d. In such micro-structures the aggregates 
formed from the primary and eutectic austenite preserve to a large extent 
their original boundaries and are thus distinguishable. The transformation 
products of primary and eutectic austenite are, therefore, designated re- 
spectively, primauBtenoid and eutectic-auttenoid. 

Sujiplementary Diagrams and Table. Fig. 3 represents in dia- 
grammatic form the micro-structures of the steel-white cast iron se asries 
observed at ordinary temperatures after slow cooling. Fig. 4 represents the 
percentages of pearlite and free ferrite and cementite, as well as of the various 
aggregates suoh as primaustenoid, eutectic, etc. 

The oonetitutaon of an alloy of any given carbon content is measured by the 



86 /RO,V AND STESL 

intercepts oF the v&rioua aresa on the ooFreaponding ordinBte. Tkble 1 givM 

the percentaeel o! these coDalitueDta ncd bIw of the ultim&te micro-con- 
Htituonta fenite and oementite. 




QiKI CftBt Iron Btritl. Cementite haa a tendency to deoonipoBe into iron 
, and graphitic carbon according to tlie equation FeiC - 3Fe + C, Thia 
tendency increasea with increase in (cmperature and increase in the percent- 
ages of carbou and silicon; the (eudeucy ie decreased by the presence of 



sulphur and usually by that of manganese. The carbon set tree by this d«ooii). 
position may take the form o( plates or of compact rounded particles, the 
shape being influenced by the temperature of formation or by the presence of 
other elements. Details of this scries are considered under cast iron, p. 1 12. 



CHEMISTRY OF PURIFICATION PROCESSES 



87 



Outline of the Oonstitution of Iron 

Table 1. Theoretical Constitution of the Pearlitiferous Series, 
Slowly Cooled Carbon Steel, and 'White Cast Iron 











Proximate composition, per cent 






Nftme 


• 
•*• 


! 

3 


>-eutectoid 
rrite 


ctoid 

ite 


1 
s 


s 


S 


5 




5 


B 




&4 A) 




3 




o o 

II 


tectic 
ment 


93 « 

as 


3 


8 

is 




sg. 


O. 1 


S»2 


ci 


^ 


3 


='« 


^ 9 


■eg 


o 


0-2 




o** 


H 1 


fk' 


ft,® 


fti 


u 






ft. 


H 


H*^ 


Low 
carbon 

» 


0.0 





100 


] 















100.0 





0.10 


11 


89 


















98.5 


1.5 


0.20 


22 


78 


























97.0 ! 3.0 






0.30 


33 


67 













95.5 4.5 




■\  - j:.. 


0.40 


44 


56 















94.0 


6.0 




Meoium A CA 
carbon ^j^ 


56 


44 









1 





0' 92.5 


7.5 




67 


33 









1 








91.0 


9.0 




• 


0.70 


78 


22 






1 



















89.5 10.5 






0.80 


89 


11 


100 





88.0 


12.0 






0.90 


100 
























86.5 


13.5 






1.00 


98 





2 


















85.0 


15.0 






1.10 


97 





3 


















83.5 


16.5 


Steel 


, 1.20 


95 





5 












82.0 


18.0 






1.30 


93 


 


7 















80.5 


19.5 




High 
carbon 


1.40 


91 





9 


















79.0 


21.0 




1.50 


90 





10 















77.5 


22.5 




1.60 


88 





12 















76.0 


24.0 






1.70 


86 





13.9, 




100 














74.5 


25.5 






1.80 


84 





13.6 


96 


4 


2 


2 





73.0 


27.0 






1.90 


83 





13.3 


92 


8 


4 


4 





71.5 


28.5 






2.00 


81 





13.1 


89 


11 


5 


6 





70.0 


30.0 






2.10 


79 





12.8 


85 


15 


7 


8 





68.5 


31.5 






2.20 


77 





12.5 


• 81 


J9 


9 

11 


10 
12 






67.0 


33.0 




«» 


2.30 


76 





12.2 


77 


23 


65.5 


34.5 


1 


2.40 


74 





11.9 


73 


27 


13 


14 





64.0 


36.0 






2.50 


72 





11.7 


69 


31 


15 


16 





62.5 


37.5 






2.75 


68 





11.0 


60 


40 


19 


21 





58.75 


41.25 






3.00 


64 





10.3 


50 


50 ; 24 


26 


55.0 


45.0 


White 




3.25 


59 





9.6 


40 


60 29 


31 


51.25 


48.75 


cast 




3.50 


55 





8.9 


30 


70 ' 34 


36 


0; 47.5 


52.5 


iron 




3.75 


51 





8.2 


21 


79 ; 38 


41 





43.75 


56.25 






4 00 


46 





7.5 


12 


88 


42 


46 





40.0 


60.0 






4.30 


41 





6.6 





100 < 48 


52 





35.5 


64.5 






4.50 


38 





6.1 





92 ' 44 


48 


8 


32.5 


67.5 






AM 


32 





5.2 





79 , 39 


41 


21 


28.0 72.0 


i 


6.67 


i 





0.0 














100 


0.0 jlOO.O 



CHEMISTRY OF THK PURIFICATION OR CONVERSION 

PROCESSES 

In the vsriouB processes for the conversion of pig iron into wrought iron or 
steel, certain chemical principles are of general application. Pig iron is 
converted to wrought iron or steel by the removal of some or all of five 
elements, carbon, silicon, manganese, sulphur and phosphorus. Percenta^jres 
of theee elements which are unobjectionable in foundry irons are detrimental 
in WTOueht iron or steel. 

In all oi these processes, the removal of objectionable elements is 
effected by their oxidation and by removal of the resulting oxides by Toi»- 



88 IRON AND STEBL 

tilixation or by absorption in the slag. The oxidising agent in all cases, is 
oxide of iron. Though in some cases, an air blast furnishes the necessao' 
oxygen, its action produces oxide of iron, which reacts with the elements that 
are to be removed, oxidising them and being itself reduced. The essential 
differences between the various purification processes are differences in the 
temperature and duration o( the reaction and in the composition of the slag. 

The temperature of the purification proeese has a great effect on the 
relative affinity of oxygen for the elements that are to be removed. At 
relatively low temperatures oxygen combines with silicon, manganese and 
phosphorus in preference to carbon. As the temperature rises, however, the 
affinity of carbon for oxygen increases until it exceeds that of the other 
elements; at high temperatures, carbon can reduce the oxides of nearly all 
elements, especially in the presence of a metal such as iron which dissolves 
the reduced elements. 

The composition of the slag greatly influences removal of some of 
these elements, especially sulphur and phosphorus; the sulphur and phos- 
phorus are readily taken up by a basic but not by an acid slag. 

WBOUOHT IRON 

In contrast to pig iron, which is brittle at all temperatures up to the 
melting point, wrought iron when heated to redness can be worked into 
almost any desired shape. This difference in properties is due to the greater 
purity of the wrought iron, and especially to its lower carbon content. While 
pig iron has about 4 per cent carbon, wrought iron usually has not more than 
0.15 per cent. From ancient to modern times wrought iron has been made 
directly from the ore. As the original low Catalan forges or bloomeries were 
gradually replaced by shafts of increasing height, manufacture of direct 
wrought iron gradually ceased. Nearly all wrought iron in the United States 
is now made from pig iron by the puddling process. A small amount of 
wrought iron in this country and a large amount in some European countries 
is made from pig iron by one of the charcoal hearth processes. 

Puddling ProccM. In this process, the pig iron generally used is "gray 
forge" iron. Its composition is: Si, 0.75 to 1.25 per cent; S, 0.04 to 0.1 
per cent; P, 0.3 to 0.4 per cent; Mn 0.5 to 1.0 per cent. The furnace is 
of the reverberatory type. The hearth is usually about 4 by 6 ft. and holds 
about 500 lbs. pig iron, though some furnaces have a capacity of about 1500 
lbs. The hearth is lined with oxide of iron in the form of mill cinder, ore or 
scale, which furnishes some of the required oxygen. The purification of the 
iron takes place in three stages. In the melting Stage, about ^i hour, moat 
of the silicon and manganese and some of the phosphorus are removed. In 
the (dealing stage, about 10 minutes, iron oxide in the iorm of scale or 
high-grade ore is added and the charge is stirred and cooled. At the lowered 
temperature, the highly basic slag oxidizes and absorbs the other impurities 
in preference to the carbon. Carbon then begins to be oxidised with libera- 
tion of carbon monoxide, causing the "boil." During the boil which lasts 
about 25 minutes, the mass is stirred or "rabbled" with a hoe shaped imple- 
ment known as the "rabble." With removal of the carbon, the meltine 
point rises as indicated in Fig. 2, until finally a pasty mass is formed when 
the iron is said to have "come to nature." 

The pasty iron is now collected into balls weighing about 80 lbs. and either 
squeesed in a rotary squeeser or hammered to squeeae out the excess slag. 
The blooms are then rolled out into bars about 3 to 6 in. wide, ^ in. thick 



WROUGHT IRON 89 

and 15 to 30 ft. long, known as "muck bar." For further removal of slag, 
the muck ban are cut into pieoes about 3^ ft. long,* wired together in f agoti, 
reheated to welding heat, and rolled into bars, sheets, plates, etc. It is now 
knoim as "merchant iroik"or "single refined iron." Sometimes 
"mereliant bars" are cut, piled, reheated and roiled to form "double 
refined iron." 

Wrought iron made from the product of the charcoal blast furnace is 
known as "charcoal iron." It is of better quality than iron from coke 
pig, which is known as "common iron." In the United States much 
wrought iron is made by piling wrought iron scrap, heating to welding tem- 
perature, and rolling into bars called "puddle bar." Sometimes small 
pieces of wrought iron and steel known as "busheled scrap" are rolled with 
larger pieces to form bars of an inferior grade of wrought iron. 

Charcoal Hearth Frooesses. In the Stsman, Walloon, Lancashire and 
other proceeses, charcoal pig iron is heated in a low hearth with charcoal as 
fuel. The pig iron, though it rests on charcoal, is surrounded by an oxidising 
atmospheare due to the air blast from one or two tuyeres. During the gradual 
melting the impurities are largely removed by oxidation and the iron covered 
with slag falls into the hearth where further purification takes place during 
the stirring of the pasty mass. It is then raised above the tuyeree, remelted 
and collected in the hearth. Since most of the slag is now on the surface, the 
mass is not stirred unless it is to be remelted a second time above the tuyeres. 
Wrought iron made by a charcoal hearth process contains less slag than pud- 
dled iron. The best quality of wrought iron, such as the well-known Swedish 
iron and the "knobbled chafcoal iron," is made by charcoal hearth 
piucesses. 

Ptopertios of Wrought Iron. Wrought iron melts at approximately 
2700 deg. F. At white heat it is readily welded. It has the following 
ptaysteal properties : Tensile and Compressive strength 40,000 to 54,000; 
elsstic limit in tension about 30,000, in torsion about 20,0()0; modulus of 
elasticity in tension 28,000,000, in torsion 12,800,000; elongation in 8 in.. 
20 to 28 per cent; reduction of area.30 to 50 per cent. It has a well defined 
yield point and fibrous fracture. Since it resists corrosion better than 
steel, it is much used in machines or structures where corrosion is of impor- 
tance. When polished wrought iron is examined mioroscopically, many 
particles of slag are visible. In addition to the slag particles, the etched sui^ 
face also shows the micro^structure of low carbon steel as illustrated in 
Kg. 3. 

Marine Uses. Wrought iron was formerly used in moving parts of ma- 
chinery requiring strength and toughness. It has now been almost entirely 
replaced by steel. It is still used to some extent in boiler stay bolts and braces, 
rivets, lapwelded boiler tubes, etc. It is still used for shafting of many 
merchant vessels. Wrought iron is used for plates which require ability 
to resist corrosion. It is also used for the manufacture of the best tool steel 
by the crucible process. Until the recent development of cast steel anchor 
chains, these were made of wrought iron. 

8TIBL 
The Bessemer Process 

Until the invention of this process in 1856, practically all steel was made by 
the recarburisation of wrought iron by either the cementation or crucible 
process. Departing from the chronological order, however, a description will 
first be given of the Bessemer process. In this process, molten pig-iron is 



90 IRON AND 8TBEL 

subjected to the action of an air blast which oxidises the impurities. Although 
the melting point rises albout 400 deg. C. in the course of the purification, the 
heat of combustion of the impurities is sufficient to keep the metal molten. 

The molten iron is contained in a "oonTertar," a pear-shaped vessel open 
at the smaller end and supported on trunnions perpendicular to its long azis.- 
In the large end, or sometimes in the side, are tuydres through which the air 
blast enters. In "blowing/' thereon verter is turned so that the small end is 
upward; in charging it is turned so that the moHen metal does not cover 
the tuyeres before the blast is turned on. The lining is siliceous or basic 
according as the acid BcMemer or the basic Bememer process is to be used. - 

Acid Bessemer Process. In this process, the converter is lined with sili-' 
ceous material, which is unaffected by the acid silicate slag produced by the 
oxidation of the silicon and other impurities of the pig-iron. Since, under these 
conditions, no phosphorus and sulphur are removed, ** Bessemer pig-iron" 
must not contain over 0.09 per cent phosphorus and 0.05 per cent sulphur. 
Since the oxidation of bilicon is the chief source of heat, the iron must contain 
not less than about 1 per cent of this element; it may contain as. much as 
2.5 per cent. Though the requirements for manganese are not very strict, 
the usual maximum in American and English practice is about 0.8 per cent, 
while in Swedish practice about 2.5 per cent may be used. 

The "Blow." In the Bessemer process, usually no attempt is made to 
stop the blow before practically all the impurities have been removed. The 
order of oxidation of the various impurities, depends not only on their relative 
chemical affinities, but also on their relative quantities and on the temperature. 
Since, the element iron is the chief chemical constituent of pig-iron, iron oxide 
is the chief oxide formed by the direct action of the air blast. As explained 
on p. 88, the iron oxide acts as a carrier of oxygen to the other elements, 
oxidizing them and being itself reduced. In the first five minutes of the blow, 
known as the slag forming period, most of the silicon and manganese are 
thus oxidized and unite with some iron oxide to form a slag. The oxidation 
of the carbon then begins, carbon monoxide being formed in large quantities 
and burning at the mouth of the converter. In this period, known as the 
"boil/* the flame, which is at first short and orange colored, lengthens and 
becomes white and dassling. When the carbon, with the remainder of the 
manganese and silicon, have thus been removed, the flanaie "drops." The 
converter is then turned down and the blast is stopped. 

Control of Temperature. If, during the blow, the metal gets too hot, 
the boil becomes too active, causing troublesome spattering and over-oxida- 
tion; if the temperature falls too low, the metal cannot be poured readily into 
moulds. To lower the temperature, solid scrap may be added, or steam 
may be blown into the converter. To raise the temperature, the converter 
may be tilted until some of the tuyeres are above the suHace of the metal ; 
this results in oxidation of iron and carbon monoxide and the production of 
additional heat within the vessel. In America, though pig-iron contiUnins 
relatively low percentages of silicon and manganese is used, the temperatrnie 
is kept up by running the heats in such rapid succession that the loss of heci't 
from the converter is minimized. 

Deoxidation. "Blown metal*' is "red short" on account of excess of 
iron oxide. It evolves gases in such quantities that it cannot produce sound. 
ingots or castings. To remove the excess oxygen, therefore, deozidisers 
are added. Of these, the most important are ferro-manganese and. 
Spiegel-eisen. Fcrro-manganese, since it contains about four times as muoli 



STEEL 91 

manganese and about the same amount of carbon as spiegel-eisen, is used 
when low carbon steel is to be made. Since spiegel-eisen, must be used in 
relatively large quantities, it is melted before addition. Ferro-Bilicon 
and lilLco-Bpiegel are also frequently used as deoxidants. Though occa- 
sionally aluminum is used, its use is limited, since its oxide tends to remain 
in the metal as small, hard particles which weaken the metal. 

Becarburiiation. Some <rf the above mentioned deoxidants, especially 
ferro-manganese and si»egel-eisen serve also to raise the carbon content of the 
metal to the required point. For this reason, they are usually known as 
"rocarburlxorB. " If additional carbon is needed, low phosphorous pie-iron« 
coke or anthracite may be added. 

B»aic Benem«r Proe«88. In this process, lime is added to the molten 
pig-iron in order to form a basic slag. To prevent corrosion, the converter 
lining must also be basic. The bc»ic slag in the presence of iron oxide is able 
to remove most of the phosphorus as calcium phosphate. Though part of the 
sulphur also is removed, its removal is less certain than that of phosphorus. - 
As in the blast furnace process, the sulphur appears to be removed in the form 
of calcium sulphide. To prevent corrosion of the basic lining by silica, the 
percentage of silicon in the pig-iron should be as low as possible, and not more 
than 1 i>er cent. To compensate for the loss of this heat forming element, the 
percentage of phosphorus in basic Bessemer pig-iron must be high, from 
2.5-3.0 per cent. Since there are no low-silicon, high-phosphorus ores in the 
United States, the basic Bessemer process is not used-ln this country. Ger- 
many is the only country that makes extensive use of the process. 

The " blow*' is similar to that of the acid process except that it is continued 
for three or four minutes after the drop of the flame. In this "after-blow" 
most of the phosphorus and some sulphur are removed. The end of the 
*'after-Uow" is determined by the appearance of the fracture of test specimens 
taken from the converter. The recarburization is similar to that of the acid 
proceas except that the recarburiser is added not to the converter but to the 
ladle. 

Bottom and Side-blown Conyerten. In the manufacture of steel to 
supply rolling mills, a bottom-blown converter holding about 20 tons is used; 
this ia able to take care of the product of two blast furnaces. Molten pig- 
• iron direct from the blast furnace is placed in a large vessel called a " mixer ;" 
from there it is drawn as needed for the converter. For making steel castings, 
a converter holding one or two tons is used. Though sometimes this "baby 
Bessemer" conTorter is bottom blown, it is more usually side blown. To 
supply these converters, pig-iron is melted with coke in a cupola. 

In the bottom-blown converter, the air bubbles through the metal, stir- 
ring it and oxidising it pniformly throughout. In the side-blown converter, 
the air blast impinges on the surface of the slag and oxidation of the metal 
oecurs chiefly near the top. For this reason, the course of the "blow" is 
not so regular in the side-Mown as in the bottom- blown converter; there may 
be several periods of *'boil" and "drop of the flame" before purification 
is complete. 

Uses of Bessemer Steel. It is generalise recognised that Bessemer steel 
is inferior in quality to open-hearth steel. For this reason its use in steel 
rails is rapidly decreasing. Though used in structural shapes for buildings 
it is no longer permitted in structural shapes for bridges and ships. In the 
Navy, its use is limited to steel castings, material for boiler plates, bolts and 
rivets, etc., where great strength is not required. 



92 IRON AND BTESL 

The Open Hearth Proeen 

In this process, the metal is purified in the shallow hearth of a reverberatory 
furnace of the regenerative type. At one end of the furnace are two chambers 
filled with checker work of fire brick, in which the air and gas are preheated on 
their way to the furnace. At the other end are similar chambers in which the 
products of combustion give up a large part of their heat on the way to the 
stack. By frequent reversal of the flow of gases, the temperature of the 
entering gases is kept at about 1800 deg. F. In some plants, natural gas or 
oil are used as fuel; in that case, only the air is preheated. Recently also 
powdered coal has been successfully used as fuel. 

The oxygen for the oxidation of the impurities in the metal comes partly 
from the air and partly from the iron ore. The purification depends also 
largely on the character of the slag. In the basic process, since a basic 
lining is used, the slag may be made so strongly basic that it can absorb 
nearly all the phosphorus and a large part of the sulphur. In the acid process, 
since the lining and consequently the slag are acidic, neither of these elements 
is removed. 

The standard open hearth furnace has a capacity of 50 to 80 tons. In a 
50 ton furnace, the hearth is about 30 to 35 ft. long, 12 to 15 ft. wide, and 18 
to 24 in. deep. For making steel castings and special steels smaller furnaces 
may be used. Though 15 tons is the smallest eco^mical size, furnaces of 
only 5 tons capacity are used. Some furnaces are so constructed that the 
hearth can be tilted enough to pour out the finished metal; all trouble with 
a tapping hole are thus avoided. 

Acid Procett. In the United States, the charge consists of two-thirds to 
three-fourths scrap and the rest pig iron. The carbon, silicon and manganese 
in the charge may vary within wide limits. Since no phosphorus and sul- 
phur are removed in this process, the charge must not contain more than about 
0.935 per cent phosphorus and 0.04 per cent sulphur. The percentages of 
these two elements will increase somewhat during the purification on account 
of the removal of silicon, manganese, etc. The percentage of sulphur is also 
increased slightly by absorption from the fuel, if producer gas is used. 

If the charge has been properly proportioned, most of the silicon and man- 
ganese and about two-thirds of the carbon will have been removed during the 
melting. The oxides of silicon and manganese, together with some iron oxide, 
combine to form a slag which floats on the suriace of the metal. To reduce 
the percentage of carbon to the required value, and to remove the remainder 
of the silicon and manganeee, ore may now be added. This oxidises the 
carbon to carbon monoxide which bubbles through the molten mass an<il 
escapes. The reaction is allowed to proceed until the carbon is slightly 
below the required value. No ore is added dtuing the last hour or two lest 
the metal be over oxidised. 

As in the Bessemer process, the steel at the end of the purification contains 
excess of oxides which must be removed by the addition of deoxidante. The 
carbon and other constituents must also be raised to the desired percentages. 
Both these reactions are efiFected by the addition of recarburisers as in the 
Bessemer process. , 

Basic Proceu. In this process, limestone or burnt lime is added to form 
a basic slag. If the basicity is kept high enough, it is thus possible to remove 
near^ all the phosphorus even when the percentage in the charge is as high 
as 2 per cent. Since the removal of sulphur is less complete than that of 
phosphorus the charge should not contain more than 0.05 or 0.06 per cent 
of this element. The silicon in the charge should not be higher than 1 per 



8TBBL 08 

cent, otherwise an ezoeositre quantity of lime will be required. It is ad- 
visable to have at least 1 per cent of manganese in the charge, since this 
dement tends to prevent over-oxidation and aids in the removal of sulphur. 
The proportions of pig iron and scrap vary greatly. 

If the quantity of lime is large enough in the beginning, the greater part of 
the phosphorus wiU be removed during the melting. After the melting is 
complete, ore is added as required to remove carbon and the remaining im- 
purities. The removal of the phosphorus is usually incomplete until the 
carbon has reached a low peroentage. In this respect the open hearth process 
occupies an intermediate position between that of the puddling and basic 
Bessemer processes. Even when high carbon steel is to be made, therefore, 
it is usually necessary to reduce the carbon percentage to a low value and then 
add sufficient recarburixer to bring the carbon up to the required peroentage. 
Sulphur, in the open hearth as in the blast furnace process, is removed 
chiefly as calcium sulphide. The more bftsic and the more liquid the 
fllaiTf the more efficient it is in the remoWi of mlphur. For this reason, 
compounds such as calcium chloride or calcium fluoride are sometimes 
added to increase the fluidity of the slag without increasing its basicity. 
The usual range of slag ccnnposition in the acid and basic open hearth pro- 
is shown in Table 2. * 



Table S. — Slag Composition 

Aoid open hearth, Basic open hearth, 

per cent per oent 

BlOt 48 to 55 10 to 25 

PbOi 6 to 15 

FeO 23 to 34 10 to 25 

MnO 13 to 21 

CaO 35 to 50 

MsO 6 to 10 

AljOi 

In the acid slag, the percentage of silica normally never varies far from 50; iron and 
Biangancae oxides together niaae up nearly all the remainder. 

The time required tor the melting and purification of the metal is 
from 10 to 16 hours. This time may be shortened by increasing the ore 
additions and, at the end of the purification, adding an increased quantity of 
recarburiser. This hastening, however, is at the expense of the quality of 
the metaL To produce good results, time is required for the oxides and other 
impurities in dilute solution to react on each other. The long time required 
for this reaction to take place is the chief reason for the superiority of open 
hearth over Bessemer steel. Since the conditions in the acid process do not 
produce so oxidising a slag as in the basic process, acid steel is usually better 
than basic steel in spite of the fact that the basic steel is usually freer from phos- 
phorus and sulphur. For example, the specifications of the A.S.T.M. for 
many kinds of steel allow 0.01 per cent more phosphorus in acid than in 
bade steel. 

There are a number of modifications of the open hearth process. Of 
theee the Talbot proeesi is one of the most important. In this process, a 
basic lined, tilting furnace of over 200 tons capacity is used. The operation 
is continuous, the furnace being emptied only about once a week. After 
purification of the first charge as usual, the greater part of the slag is poured 
off; then about a third of the metal is poured into the ladle and recarburised. 
To the remaining metal, iron ore and limestone are added to form a basic, 
highly oxidised slag; pig iron is then added to replace the metal that has been 
TCmoved. 



94 IRON AND STEEL 

Although the reaction is very ytgoroufl, the mixture does not boil over, 
since the pig iron is considerably diluted by the previously purified metal. 
In this process, therefore, steel can be made from pig iron alone. The rapidity 
of the purification makes it possible to obtain three or four heats of about 75 
tons each in 24 hours. 

There are processes in which the metal is given a preliminary troatmont 
to remove part of the impurities and is freed from the preliminary slag. It 
is then given final purification either in the same hearth or after transfer 
to a different hearth. Of these processes, the most important are the Camp- 
bell No. 1, the Campbell No. S, and the Bortrand-Thiel procoaset. 
These will not be described. 

Duplex ProeesMi. When an ore has too high a percentage of silicon 
for use in the basic open hearth process, it is sometimes given a preliminaiy 
treatment in the acid Bessemer converter to remove the greater part of the 
silicon and manganese. The metal in the molten condition is now transferred 
to the basic open hearth and purified in the usual way. Although the ooet 
of the duplex process is greater than that of either the Bessemer or open hearth 
processes alone, the increased cost is made necessary in some localities such 
as Alabama, where ores and coke are both of such quality that it is difficult 
to make pig iron that will conform to the requirements of the basic open hearth 
process. The duplex process makes it possible to use pig iron of high silicon 
content. As explained on p. 81, such pig iron, if properly made, has a low 
percentage of sulphur. 

The Cementation Proceu 

As used for several centuries, this process consists in heating wrought iron 
in contact with charcoal. The wrought iron in the form of flat bars is em* 
bedded in charcoal in cast iron boxes about 8 to 15 ft. long, and 2^ ft. wide 
and deep; the material is then heated in furnaces at about 1000 deg. C. The 
carbon of the charcoal gradually penetrates the iron to a depth depending on 
the temperature and time; for complete carbonization, 7 to 11 days are re- 
quired. The progress of the reaction is observed by removing test pieces, 
breaking them and noting the appearance of the fracture. The bars are then 
allowed to cool in the furnace. 

The bars now have a blistered appearance, on account of which the material 
is called "blister bar" or "blister steel." In order to make the carbon 
distribution more uniform, the bars are usually piled in fagots, reheated and 
rolled. The material is now called "single shear steel." Sometimes these 
bars are again piled, reheated and to form "double shear steel." 

Since this process requires so long a time, and since even the "double shear 
steel" is not of uniform carbon content, the cementation process has been 
gradually replaced by the crucible process. 

For surface carbonization or "case hardening," however, the cementation 
process is still of great use. Details of this process will be given later. 

The Crucible Process 

This method has been in use in the Orient since ancient times. In England 
the process was first used by Huntsman in 1740. He melted blister bars in 
crucibles and thus produced a much more uniform material than could be 
produced by the cementation process alone. The process in this form is still 
in use at Sheffield, England. In the United States, however, the long prelimi~ 
nary cementation is omitted; the wrought iron is simply melted in crucibles 
with the requisite amount of charcoal or other carbonizing material. 



STBSL 95 

The crucibles hold about 60 lb. each. In England, they are made of fire 
clay; in the United States, they are usually made of a mixture of fire day and 
graphite. The fuel used in England is generally coke; in the United States 
coal or gas is commonly used, though there are some oil burning fumaoee. 
If gas is used, the furnace is of the reverberatory type. 

Since the crucibles are kept tightly covered, the atmosphere in contact 
with the steel, though at first oxidising, soon becomes neutral or even reducing. 
One of the great advantages of this process, therefore, is that plenty of time may 
be given for the removal of oxides and other non-metallic inclusions. In 
other words, the reaction between iron oxide and carbon proceeds nearly to 
completion. Under these conditions, the carbon of the steel also reduces more 
or less silica to silicon, which is absorbed by the steel. Crucible steel, 
therefore, usually contains from 0.1 to 0.5 per cent silicon; this tends to pre- 
vent the formation of blow holes in the castings. If the " killing'* of the steel 
is aUowed to proceed too far, however, the steel becomes brittle from excess 
of silicon. 

While in Sheffield charcoal hearth iron is used for the best grade of tool 
steel, in the United States puddled iron is generally used for this purpose. 
The use of basic open hearth scrap in the crucible process results in an inferior 
material. The reason for this inferiority is not clearly understood, since basic 
open hearth scrap may be apparently purer than wrought iron. Though open 
hearth scrap is not suitable for the manufacture of tool steel, it is good enough 
for the production of steel castings for many purposes. Crucible steel , if prop- 
erly made, is superior to any except electric furnace steel. 

The Electro-thermic Proceu 

Electro-thermic heating has important advantagBB over other methods. In 
the electric furnace, the temperature can be brought high enough to maintain 
fluidity in a slag richer in lime than are the slags used in other steel making 
processes; this facilitates the removal of impurities from the metal. More- 
over, since combustion is not the direct source of heat, the metal can be kept 
free from the contaminating effect of the products of combustion. An oxi- 
dising atmosphere within the furnace can also be avoided. 

The electric furnace has its chief field of ueef ulncM in the production 
of steel from high grade scrap and pig iron, or in the final purification of steel 
that has been partially purified by one of the other steel making processes. 
Since electric energy as a direct source of heat usually costs more than fuel, 
the electric furnace is seldom used in the production of inferior grades of steel. 
In some locaUtieB, however, where electric power is cheap, steel may be pro- 
duced from inferior grades of pig iron and scrap, and pig iron may even be 
produced from the ore. 

Electric furnaces may be classified according to the method of application 
of the electric energy. The heat mMj be supplied entirely by radiation from 
the electric arc, or partly by radiation from the arc and partly by the passage 
of the electric current through the slag and metal. Or the heat may arise 
from a current induced in the metal itself. 

In the StaHaao furnace, the metal is heated by radiation from arcs 
paasing between electrodes inserted diagonally through the sides of the furnace 
above the hearth. Generally three phase current is used, the three electrodes 
being symmetrically placed about the cylindrical furnace. 

In the Heroult furnace, two or more electrodes are inserted vertically 
through the roof. The current passes by arc from one or more of these 
dectrodes down through the slag to the metal beneath, thence through the 



96 IRON AND STEEL 

metal and by one or more arcs to the remaining electrodes. In this iumace, 
therefore, the current pasees through two arcs in series. 

In the Oirod f umaoe, the current enters through one or more electrodes 
inserted vertically through the roof; thence it passes through one or more 
arcs in parallel to the surface of the metal and down through the metal to 
electrodes inserted through the bottom of the furnace. 

In induction fumaces such as the Xjellin, no electrodes are used. A 
current is induced in a closed circuit of molten metal so arranged that it con- 
stitutes the secondary coil of a transformer. 

This circuit of metal encloses an arm of the magnetic circuit abott which 
is wound the primary coil carrying alternating current. As in ordinary 
transformers, the voltage of the induced current varies inversely, and the 
strength of the induced current varies directly as the number of turns in the 
primary coil. A disadvantage of this furnace is the ringnshaped hearth, which 
is unsuited for the purification of metab. For this reason the furnace is 
suited only for the melting of metal when little or no purification is required. 

The disadvantages of the ordinary induction fiirnace have been overcome 
in the Boohling-Bodenhauser furnace. In this furnace each arm of the 
magnetic core is surrounded by a ring-shaped hearth; the two rings meet so 
as to form a central hearth large enough to permit of the purification of the 
metal therein. This central hearth receives additional heat from current in- 
duced in a secondaiy coil surrounding each arm of the magnetic circuit. The 
furnace is thus a combination induction and resistance furnace. 

The Qin furnace consists of a long trough, usually of winding shape so as 
to permit of greater length, through which current passes and furnishes the 
required heat. On account of the unsuitability of this shape for metallur- 
gical work, this form of furnace is little used in steel making. 

Acid Uned f umacci are used in simple remelting processes, in which no 
removal of phosphorus or sulphur i^ required. In such furnaces, scrap and 
pig iron of a high degree of purity are melted, brought to the required 
percentages of carbon, silicon, and alloy constituents, and held until deozida- 
tion has been completed. The atmosphere of the electric furnace, unlike 
that of the open hearth, can be made neutral or even reducing in character, 
and the metal can be held in this atmosphere as long as desired. 

Basic lined furnaces may be used for removing phosphorus and sulphur 
as well as other elements. For this purpose, it is better to use metal that has 
been treated by one of the other steel making processes so that the electric 
energy may be utilized only for the final purification of the metal. Prefer- 
ably also the metal should be charged in the molten condition in order to 
conserve electric energy. 

Chemistry of the Electro-thermic Process. The high available tem- 
I)erature and the ready control of the atmosphere within the furnace make 
the electro-thermic process of great value in the production of steel that is 
relatively free from phosphorus, oxides and sulphides. The conditions re- 
qtiired for the removal of phosphorus differ entirely from those required for 
the removal of sulphur. While phosphorus is removed in the form of phos- 
phates and therefore requires oxidizing conditions, sulphur is removed as cal- 
cium sulphide and therefore requires reducing conditions. For these reasons, 
it is necessary, after adjusting the conditions for the removal of one of these 
elements,t o remove the slag containing this element and change the ooi>- 
ditions so as to favor the removal of the other element. 

Usually the phosphorus is removed first. If sulphur is to be removed first. 



STBBL-INOOTS 97 

the metal must be deozidiaed and fraed from sulphur, reozidiied lor tlio re- 
moval of phosphorus, and again deozidiaed and recarburiaed. Thia prooed- 
ure would require an excessive quantity of ferro-eilioon. The prior removal of 
the sulphur is economical only when low silioon steel is to be made from metal 
that has been deoxidised by one of the other steel making processes. 

Instead of treating the metal in the electric furnace with two or more slags 
as described above, the use of duplex or triplex processes is finding increasing 
favor. This procedure involves a preliminary treatment of the metal either 
in the basic open hearth or in the Bessemer converter followed by the basic 
open hearth. The greater part of the impiu-ities are thus eliminated before 
&e metal is transferred to the electric furnace. 

Steel properly made by an electro-thermic process has better phjrsical 
properties than that made by any other process. On account of its freedom 
from non-metallio inclusions its endurance when subjected to repeated or 
alternating stresses is especially good. 

TI16 B«U-Xrupp Proceu 

This is one of the most important processes for the partial purification of 
IMg m>n. In this process, molten pig iron is stirred in contact with iron oxide. 
The temperature is kept so low that the slag, rich in iron oxide, oxidises and 
removes from the metal most of the silioon and phosphorus without re- 
moving much of the carbon. The iron ore is heated in a sHghtly inclined 
revolving hearth furnace. Liquid pig iron is then added. After about five 
minutes, most of the silioon and phosphorus have been removed and the 
oxidation of the carbon begins. The furnace may be tapped at this point 
or, if more thorough removal of phosphorus is desired, the process may be 
continued for three to five minutes longer. 

In the product, known as "washed metal," the sulphur and phosphorus 
peroentagiBs do not usually exceed 0.03 and 0.025 respectively. Washed 
metal is used in crucible steel making and in foundry practice as a means of 
adjusting the carbon content in castings. 

nffooTS 

Pipes. Since steel on solidifying decreases in volume, and since the upper 
and inner portion of a top poured ingot is usually the last to solidify, the upper 
surface of the metal usually settles and forms a "pipe." If this downward 
flow is prevented, one or more closed cavities occur along the axis of the ingot. 
To diminish piping, many devices are used to delay the solidification of the 
upper port of the ingot and thus permit downward flow of the metal. The 
**pipe" is diminished by using a tai>ered ingot mold with large end up. 

Blow holes in steel are due to the entrapping of gases evolved from the 
■olidifying metal. These gases are usually due to the interaction of oxides 
with the carbon of the steel to form carbon monoxide. Though sometimes 
blow holes are purposely allowed to form in order to dimifush piping, this 
method of prevention results in an inferior quality of steel. Usually blow 
holes are eliminated as much as possible by the addition of deoiidiling 
agents such as ferro-manganese, ferro-silicon, ferro- titanium, aluminum, etc., 
as described under the various processes of manufacture. 

Segrefation. As illustrated by the iron-carbon equilibrium diagram. 
Fig. 2, during solidification the solid metal contains less carbon than the 
molten metal with which it is in equilibrium. The percentages of solid and 
liquid respectively at any temperature are represented by the abscissas of 
isothermal points on the "solidus" and **liquidus." Since the residual 
7 



^ IROff AND STEEL 

liquid beoomes continaally richer in carbon, there is segregation of this 
element in the regions near the top and center of the ingot. For similar rea^ 
sons there is segregation in the same region of impurities such as phosphonis 
and sulphur. Since this region contains defective material, the top portion 
of the ingot is removed whenever possible by "cropping." Although the 
most defective metal is removed by this method, there still exists a certain 
amount of axial segregation resulting in deficiency in physical properties in 
that part of the ingot. 

MECHANICAL TBXATMSNT 

Ingots formed as described above are subjected while hot to various me- 
chanical processes, such as roUinCi hamznering or pressing , which not only 
give the required shape to the metal but also improve its physical properties 
by breaking up the coarse crystallisation of the original ingot. Steel objects 
of relatively simple shape, such as rails, when required in large quantities, 
are fopned by rolling. When the required shape is complex, or when a 
superior quality of material is required, the metal is forged by hammer or 
press. Pressing is more effective than hammering, since it works the 
metal to a greater depth. 

A minimum amount of working of metal is required in specifications for all 
important forgings. U. S. Naval Specifications require that the area of cross 
section of the rough forging shall be not more than one-fourth that of the 
original ingot. The amount of reduction of cross section, however, should be 
adapted to the use to which the forging is to be put; excessive reduction 
merely increases the physical properties in a longitudinal at the expense of 
those in a transverse direction. 

The best finishing temperature for hot working is just above the trans- 
formation range as shown in Fig. 2. With increase in finishing temperatiire 
above the transformation range, there is a corresponding increase in the 
grain size of the finished product. On the other hand, if the forging process 
is continued below the transformation range of temperature, it results in 
grain distortion and other embrittling efifects of cold working. For some 
purposes, such as wife, however, the metal is finished by cold drawing so 
as to produce high tensile strength even at the expense of considerable loss 
of ductility. At a " blue heat" (so named from the color of the oxide film), 
about 400 to 500 deg. C, steel is very brittle and cannot be forged without 
developing cracks. 

As shown by the micro6coi>e, the grain distortion caused by cold working 
is made possible by the slipping of the metal along various planes bearing 
definite relation to the axes of crystal symmetry. These slip lines vary- 
in number and prominence with the degree of distortion of the metal. Accord- 
ing to a widely accepted theory, amorphous metal is formed along these 
slip lines. The presence of this amorphous metal, which is hard and brittle, 
accounts for the hardening and embrittling effect of cold working. 

HSAT TREATMENT 

Grain Beflnement. The heat treatment of steel depends on the changes 
produced by heating the steel above the transition range into the austenite 
region as shown in Fig. 2, and on the reverse changes pvoduced by varying 
the rates of cooling from the austenite into the pearlite range of temperature 
and composition. To remove the coarse structure of a casting or forging, 
the metal is heated until its temperature is such that it enters the austenite 
field. In passing through the transformation range into this field, the pearlite 
is changed into austenite and the excess ferrite or cementite is gradually dis- 



I BEAT TRBATMBNT 

I >o[T«d, As looii as auat«Dite ia formedi the Braina of thia 

to grow; if therefore, the t«iD- . 

' perature ia earned too tar or fi4!»ou«. 

auntaioed too long above the h S ^ 2 o 

traiaformation range, the BUB- = I » « 

tenitegraiD BiM, and the graina "UiM** J«"-oio( - ul^>e-«'n 

rormed from the auBteiut« on 

ooolini, will be unneceaBarily 

oatiae. Id general, the t«m- 

peralure should not be more 

than about 75 deg. F. above 

the theoretical temperature aa 

■hown in Fig. 2 : thia temper- 

■hue. moreover, ahould be 

held only loog enough to com- 
plete tiie traoBformalion into 

■ustenite. The metal is then 

coded at a rate vhich dependa t 

on the phyaiol propertJM E 

dtdJMJ. 3 

AnnMlInc. Slow cooling ^ 

from above the tranaition tern- « 

persture produces pearlite ■: 2 

either alone or with free ferrite S 2 

metal ia of eutectoid. hypi>- -| 

Futectoid. or hypereutecloid J 

rampooition. Annpaliiig re- S 

lulU In ft nikilmuin of 
ductlUtr (tnd a minimum 
of tenslls atrenfth uid 
•Uatle limit; the values of 
these properties ia ancealed 
sled depend on the chemical 
composttioa. I n carbon strele. 

tfaa carbon cont«nt is the de- ratg-ajiM 

tarTDUiiag factor. The effect 

el thia element on the hard- q***'^ 
nssB. tenacity and ductility is -i i^tHL 
illostnled by Fig. 5 taken J t>4ii>1 
from "The Metallography of " 1«HPJ 
Steal and Cast Iron "by Henry simi 
M. Howe. Fig. 6 should be ».iL*mi»( 
studied in connection with unpiu^ 
Pig. 4. s?"^"^ 
Hardoninc. When at*el, '{^ 
after grain refinement as de- 
scribed above, ia cooled rapidly ^ .i^ 

throli^ the transformation ^i g g i S ,5 

raniie. the transform ation 8 S — l ^ 

from aufltenite to pearTitB ia jsqu.nM'wpJBHriwug 3^ 

partly Buppresaod. It fe im- 
poasible to prevent thia traDBformation entirely in carbon steels; if ma 



100 . IRON AND STEEL 

than 1.5 per oent oarbon is present, however, some of the austenite may be 
preserved unaltered. Alloying element s, also, such as manganese, nickel, 
etc., if present in sufficient quantity, entirely suppress the transformation. 
Under ordinary conditions, however, quenched steel contains no austenite. 
The types of microstructure resulting from cooling at various rates are 
given various names, such as mftrtensite, troottite, sorbite, sorbitlc 
pearllte, etc. The name "osmondita" has been used to designate a sup- 
posed structure between that of troostite and sorbite; various compound 
terms, also, such as "trooito-sorbite" are in use. 

The writer believes that unnecessary confusion has resulted from the at- 
tempt to draw distinction between structures separated by no apparent 
dividing line. On an etched, bar of high carbon steel, one end of which has 
been quenched in water, there is discernible a sharp line separating the struc- 
ture designated *'martensite'* from that designated "troostite." From this 
line of demarcation which is visible to the unaided eye, there is a gradual 
change from "troostite" to laminated pearlite. ^ Under the microscope, there 
are visible at this line of demarcation black lines in certain cleavage planes of 
the martensite and black nodular masses on the grain boundaries. These 
lines and masses merge gradually as the troostite field is entered until the 
whole structure consists of the dark colored constituent. Between this con- 
stituent and laminated pearlite there is no apparent dividing line. 

E^entially, therefore, the constituents of hardened steel fall^into two 
K^oups* the austenite-martensite group and the troostite-peaxlite group* In 
the former group there is a gradual change^ in structure from austenite to 
martensite- While austenite has the usual structure of an annealed solid 
solution or pure metal, quenched carbon steel rarely exhibits this structure 
unaltered* In such material lines have appeared within each grain in three 
directions corresponding to the cleavage planes of the original austenite 
grains. These lines, which frequently have the appearance of needle shaped 
crystals, are considered by some authorities to be merely twinning planes 
in the austenite. A structure in which these lines are visible in greater or less 
number and prominence is known as martensite. Its properties are very 
different from those of the original austenite; while the unaltered austenite is 
comparatively soft and ductile, the appearance of the tri-directional markings 
coincides with great increase in hardness and the development of brittleness. 

In the troostite-pearlite series, troostite (which may be considered to be 
emulsified ferrite and cementite as first formed from m£ui>ensite) is next to 
martensite in hardness. The hardness gradually diminishes with coagulation 
of the pearlite until in laminated pearlite we have only the hardness of an- 
nealed steel. At one end of the series, therefore, we have troostite; at the 
other end, laminated pearlite. 

The hardest tool steel consists of martensite at the point of transforma- 
tion into troostite. It is readily produced by quenching medium or high 
carbon steel in water. Oil quenching produces a softer structure containing 
less martensite and more troostite. Still slower rates of cooling, such as air 
cooling, produce the more or less coagulated constituents usually designated 
'* sorbite" or "sorbitic pearlite." 

Tempering. Instead of varying the rate of cooling to produce these 
metastable structures, similar results may be produced by water or oil quench- 
ing followed by reheating or "tempering" at temperatures depending on the 
properties desired. The higher the reheating temperature the farther the 
transition proceeds from austenite toward pearlite. Although this reheating 
temperature is best determined by use of a pyrometer^ it has been customary 



HEAT TRBATMBNT 



101 



to estimate it by means of a scale of *' temper colors. " These oolors, with the 
approximate correeponding temperatures, are given in Table 3 below. It 
should be noted, however, that the temper colors depend not only on the 
temperature but also on the time of heating as shown in Table 4. 

Table S. Temper Colors and Temper»tur«g 



Color 


Temperature, 
degrees C. 


Ijght Btraw 


220 to 230 


Dark straw 


240 


Yellowish brown 


255 




265 


Purple 


275 


Violet 


285 


Cornflower blue 


295 


Pale blue 


310 to 315 


fifHi green 


330 







Table 4. Temper Colors As Affected By Time 



Temperature, degrees C. 


Time of heating until color appears, minutes 


Straw 


Brown 


Purple 


Dark blue 


Pale blue 


200 

220 
250 
275 


6 
3 
1 


49 

33 

10 

3 


63 
39 
11 


27 


40 



Tempering of hardened steel is usually necessary to relieve internal stresses 
as well as to produce alterations of structure. Such internal stresses are 
caused by the fact that the transformation products occupy greater volume 
than the austenite. If these stresses are not relieved they may lead to rup- 
tare of the metal either spontaneously or under the application of stresses in 
service. ^ 

Heat Troatmont off Maehlnory Steel. The prooess of quenching and 
tempering is applied in the heat treatment not only of tool steel but also of 
many grades of carbon and alloy steels. As applied to steel other than tool 
steel it is often incorrectly designated "double annealing." The term 
"tempering** rather than "annealing** seems applicable to these steels as 
^reU as to tool steels; the term "annealing" as applied to steel should be 
reserved to mean heating above the critical range followed by slow cooling. 
On applying this heat treatment, the grain refining temperature may be 
usually obtained by reference to Fig. 2, adding about 75 degrees F. to the 
theoretical temperature. The rate of accelerated cooling (water, oil or air) 
H'will depend on the sise of the object; in general the cooling should be as rapid 
as possible with avoidance of cracking due to internal stresses. The reheat- 
IbC temperature will depend on the physical properties desired. 

A. 8. T. M. recommendations in regard to heat treatment off 
, Ctfbon steel hiCve been condensed into the following paragraphs. Except 
' fer condensation and omission few alterations have been made in the language. 
To distinguish this material, quotation marks are used. 

Boiled and Forged Objects; Methods off Heating. In case of large 
objects, the heating of the interior of which lags behind that of the outside, 
the final approach to the desired temperature should be slow. An exposure 



102 TRON AND STEEL 

of one hour at that temperature should he long enough for pieces 12 inches 
thick; thicker pieces need longer heating." 

Oraln Befining Temperature. **In general, the higher the carbon 
content, the lower should be the grain refining temperature; hence different 
temperatures are given for different ranges of carbon content. For each 
range of carbon content a range of temperature is given, the upper limit of 
which applies to larger objects and to the lower part of the corresponding 
range of carbon content. In Table 5, the temperatures are adapted for steel 
of the usual moderate manganese content. For steels with a manganese 
content higher than 0.75 per cent slightly lower temperatures suffice.*' 

Table 6. Recommended Orain Refining Temperatures 



Range of carbon content, 
per cent 


Range of temperature, 
degrees C. 


Less than 0.12 
0.12 to 0.29 
0.30 to 0.49 
0.50 to 1.00 


875to92S 
MO to 870 
815 to 840 
790 to 815 



Cooling. "After the object has been held at the grain refining tempera- 
ture long enough to make the temperature nearly uniform throughout and to 
complete the refining of the grain, it should be cooled in a way suited to its 
carbon content and to giving it the specific properties needed. To give the 
greatest softness and ductility, even at a certain sacrifice of strength and 
elastic limit, the metal should be cooled slowly either in the furnace or under 
cover of non-conducting material. To give great tensile strength and high 
elastic limit, even at a certain sacrifice of ductility, the cooling should be more 
rapid, the rate being governed by the thickness and carbon content of the 
object. To give an unusually high combination of ductility and tensile 
strength and elastic limit, the object should be quenched in oil or water and, 
if possible, removed from the quenching liquid lief ore it has cooled below 160 
deg. C. Tempering should then begin within a few hours after the quenching, 
and if possible before the piece has cooled below 100 deg. C. For very high 
elastic limit and tensile strength, the tempering should l3c at 500 to 650 deg. 
C; in this case, the ductility will be low. For intermediate properties, 
best suited to the majority of cases, the tempering should be at 600 to 650 
deg. C For greatest ductility, with good strength and elastic limit, the tem« 
pering should be at 625 to 750 deg. C." 

A. S. T. M. Recommendations For Heat Treatment of Carbon Stael 

Castings. "The castings should be heated slowly and uniformly to tem- 
peratures varying with the carbon content of the steel, approximately as 
follows: 

Carbon, per cent I Temperature, degrees C. 



Up to 0.16 
0.16 to 0.34 
0.35 to 0.54 



925 
875 
850 



0.55 to 0.79 830 



Nothing in these recommendation.^ shall ox>erate againdt the annealiag 
temperature being 50, and in special cases 100, deg. C. higher than those 
given in the table, when necessary to attain the desired result. The oastiniEB 



CHEMICAL COMPOSITION-'PHYSICAL PROPERTIES 103 

should be cooled slowly and uniformly in the fumAce when it is desired that 
^e steel possess the maximum softness. They may be cooled at an acceler- 
ated rate when it is desired that the steel possess rather higher tensile strength 
and elastic limit than can be procured by very sldw cooling." 

Orain Growth of Low Carbon Bteel. When metal that has been cold 
worked is heated to a sufficiently high temperature, new grains are formed from 
the fragments of the original grains. The lowest temperature of recrystalliza- 
tion. designated the "germinatlTe temperature/' depends on the degree 
of prior plastic deformation. The greater the previous deformation the lowei 
is the germinative temperature. Under certain conditions exaggerated 
grain growth may occur at this temperature. The conditions favoring exag- 
gerated grain growth are: the presence of only one metallographic constituent, 
temperature gradient, strain gradient, and relatively high germinative tem- 
perature. Since the two latter, conditions are most likely to occur in very 
slightly cold worked metal, exaggerated grain growth is often observed in 
such material after subjection to certain temperatures. 

In steel having more than about 0.13 per cent carbon, pearlite is present 
in sufficient quantity to hinder grain growth of the ferrite. In steel having 
between 0.04 and 0.13 per cent carbon, however, formation of enormous 
grains may occur, if it is heated to 700 to 900 deg. C, and especially if the 
temperature is long maintained. Such grain growth in low carbon steel, 
with its accompanying brittleness, is known as ''Steftd's brittlenesB." 
Heating above 900 deg. C. breaks up the coarse grains and restores the 
ductility of the steel. 

IHFLUXNCl or CHEMICAL COMPOSITION ON PHYSICAL 

PROPERTIES 

Sulphur in steel containing manganese occurs in dove gray non-metallic 
inclusions consisting largely of manganese sulphide. The effect of such 
inclusions on the physical properties of the metal depends on their number 
form and grouping. If manganese is insufficient in quantity to combine with 
the sulphur, the sulphur exists in combination with the iron as a film of iron 
sulphide on the grain boundaries. In this form it is very detrimental to the 
physical properties of the metal; it produces the effect known as "red 
•bortneu. " For the above mentioned reasons, the percentage of sulphurs 
in high grade steel is usually limited to 0.02 to 0.05. 

Phosphorutf unless in unusual quantity, occurs in steel in solid solution 
in the ferrite. It produces "cold shmrtness" or brittleness. This effect 
10 greater in high than in low carbon steel. Specifications usually limit the 
pereeotage of phosphorus to 0.02 to 0.1 depending on the quality of steel 
desired. 

Sllleon in carbon steels may occur in any percentage up to 0.5 or 0.6. The 
higher percentage is frequently found in crucible steel. In this quantity, 
silicon is not considered harmful. Silicon promotes soundness in the metal 
mther on account of its affinity for oxygen or because it increases the solubility 
of gases in the solid steel. 

Sllico-man^anese steel is a medium carbon steel containing 1 ^^ to 2 
per cent silicon. It is used in tempered gears and springs. 

Commercial higb silicon steel usually contains from 2^ to 3H P^r cent 
silicon and has a low carbon percentage. When properly quenched and 
tempered, this steel has a permeability greater than that of pure iron. This 
property, with its high electrical resistance, makes silicon steel useful in 
transformers and other electrical apparatus. 



104 



IRON AND STEEL 



Mangana— . Since manganMo as a deoxidizing agent in the steel making 
procese must be added in exoesa, practically all steel contains this element. 
If the finished steel contains less than about 0.2 per cent it usually displays 
some of the effects of ihcomplete deoxidation. Manganese increases the 
tensile strength and decreases the ductility; its effect on these properties 
increases with increase of the carbon content. If the percentage of manga- 
nese is raised above a limit of about 0.35 to 2 per cent according to the com- 
position of the steel, the steel shows hrittleneas; in high carbon steels this 
biittleness manifests itself in a tendency of the steel to crack when quenched. 
Steels containing about 2 to 6 per cent manganese aie so biittle that they may 
be pulverised by a hammer. 

Manganese lowers the temperature and retards the rate of the austenite- 
pearlite transition. As the percentage rises above about 7 per cent, this effect 
becomes so marked that, when quickly cooled, part of the steel remains in the 
austenitic state. With further increase in the percentage of manganese, the 
proportion of austenite increases, with conjsequent increase in the ductility. 
In quickly cooled steels containing about 12 to 15 per cent manganese, the 
entire structure consists of austenite. When such steels are slowly cooled, 
more or less of the austenite is changed to martensite with consequent 
decrease in the ductility and increase in the hardness. The properties of a 
series of manganese steels are given in Table 6. 





Table 6. 


Properties of Manganese Steels 






Mn 


Water quenched 


Annealed 


c 


T. S. 


Elong., 
Sin. 


T. S. 


Elong., 
8 in. 


o.si 


6.95 


51.520 


2 


47.040 


2 


0.61 


9.37 


87.360 


15 


85.120 


16 


0.85 


10.60 


89.600 


17 


91.840 


17 


1.10 


12.60 


120.960 


27 


82.880 


11 


0.92 


12.81 


136.640 


37 


107.520 


20 > 


0.85 


14.01 


150.080 


44 


107.520 


14 


1.24 


15.06 


136.640 


31 


105.280 


2 


1.S4 


18.40 


118.720 


10 


87.360 


1 


1.60 


19.10 


132.160 


4 


91.840 


1 



Austenitic manganese steel is so toujgh that it is practically unmaohinable. 
Though not intensely hard to the file, it has the property of hardening greatly 
under slight deformation such as surface abrasion; this produces a hard sur- 
face with underlying tough metal. Manganese steel is used in machinery, 
such as rock crushing machinery, requiring a combination of hardness and 
toughness. 

Nickel in steel occurs chiefly in solid solution in the ferrite; it is, therefore, 
not visible as a separate micro-constituent. Nickel raises the elastic Umit 
and to a less extent the tensile strength, with only slight decrease in tlie 
ductility. In other words, for the same ductility, nickel steels have a higher 
tensile strength and elastic ratio than carbon steels. The effect of nickel on 
these physical proi)erties, however, is less than half that of manganese. 
Nickel steel has a finer grain structure than carbon steeel; this accounts in part 
for its higher elastic limit and greater endurance. For the above reasons it 
is used in structural work such as bridges, in rails at curves, ordnance, engine 
forgings, shafting, etc. Although nickel steel in the annealed condition ia 
superior to carbon steel, the full advantage of the use of nickel is obtained 
only by quenching and tempering. 



CHEMICAL COMPOSITION'-PHYSICAL PROPERTIES 106 

like manganefle, nickel also lowers the temperature and retards the rate of 
the austenite-pearlite transition; its effect b about half that of manganese. 
Each 1 per cent of nickel up to 5 per cent lowers the transition temperature 
10 or 20 deg. C. aoeording as the transition is from pearlite to austenite or the 
reverse. In nickel as in manganese steels between certain percentage limits, 
there is a range of brittleness; this range includes steels containing from about 
8 to 15 per cent nickel. With increase of nickel above 15 per cent, austenite 
appears in quickly cooled steels, and the proportion of this constituent 
increases until in 25 per cent nickel steel the structure is entirely austenitac. 
Anstenitic nickel steels have considerable strength and ductility; they are 
used in apparatus or machinery requiring strength, toughness and resistance 
to corrosion. 

With addition of nickel to steel, the coefficient of expansion decreases until 
in the alloy known as "invar, " containing about 36 per cent nickel, the 
coefficient is practically sero. With further increase in the percentage of 
nickel, the coeffieieni gradually increases until at 42 per cent the coefficient is 
about the same as that of glass or platinum; this alloy is therefore known as 
"pUtinite." 

Chromium. This element, when present in steel, occurs partly in solid 
solution in the ferrite and partly in the cementite in the form of double car- 
bides of iron and chromium. Though chromium strengthens the ferrite of 
Bteel, in the absence of carbon it does not produce any greater hardness than 
does silicon or aluminum. Carbonless chromium steeli are not hardened 
hy water quenching. The hardness of ordinary chromium steels, therefore, is 
due to the double carbide or chromlf erouB cementite. This double carbide, 
however, produces less brittleness in chromium steels than does an equal pro- 
portion of cementite in carbon steels. In chromium steels, proper heat 
treatment will produce a combination of great hardness and toughness. 

Steel with about 0.5 per cent chromium and low carbon content is used in 
pieces that are to be case hardened; the absoprtion of carbon in this process 
fanaa a bard exterior of double carbides on a relatively soft interior. With 
about 0.35 to 1 per cent carbon, 0.5 per cent chromium steels are used in 
gean, springs, steel tires, saw blades, chisels, knives, rasors, files, etc. 

Steel with 1 to 1% per cent chromium and about 1 per cent carbon is used . 
hi ball races, cones, roller bearings, crushing machinery, safe steel, etc. 

Steel with 2 per cent chromium is used in armor piercing projectiles, 
armor plate, cold rolls, drawing dies, etc. 

Chromium steels are frequently used in the manufacture of three or five 
ply plate for plows, burglar proof safes, prison bars, etc. These plates or 
bars are made by rolling together alternate layers of chromium steel and 
wrought iron or low carbon steel, thus combining in one piece the hardness of 
diromium steel with the toughness of the softer metal. 

Chromium, unlike manganeee or nickel, slightly raises the temperature of 
the transition from pearlite to austenite. Like the former elements, however, 
ehromium greatly retards the austenite-pearlite transition. When the chro- 
aiium is increased above about 7 per cent, the structure even after slow cooling 
li martensitic. As the percentage is increased above about 12 to 15, white 
grains of the double carbides appear within the martensite. With more than 
about 20 per cent chromium, the structure consists entirely of double carbides. 

Steel having' about 12 to 15 per cent chromium is useful on account of its 
resistance to oxidation even at high temperatures. This steel, commercially 
known as "stainlMa sta^l/' is used in cutlery, valves of internal combustion i 

engines, and other objects m which similar properties are required. When 



106 * IRON AND 3TEBL 

properly treated, this steel has great strength and toughness as shown by the 
following example: Steel having 0.243 per cent carbon and 13.48 per cent 
chromium had the following physical properties: Tensile strength 107,500 lbs. 
per sq. in.; elastic limit 67,000; elongation in 2 inches, 25 pei'oent; reduction 
of area, 61.1 per cent. 

Chromium-nickel steels have the valuable properties imparted by 
chromium and nickel separately. They have a combination of high elastic 
limit, toughness and wearing qualities. They can be forged and machined 
more easily than chromium steels. Care, however, is required in forg- 
ing, and the temperature must not be allowed to fall below a bright yellow 
heat. 

These steels are usually classified as low and high chromium nickel steels. 
Low chromium-nickel steels contain 0.5 to 0.8 per cent chromium and 
about 1^ per cent nickel; in this class is "Mayarl" steel» which is made 
from a natural chromium-nickel ore. High or "full" chromium-niekel 
steels contain 1 to lli V^^ cent chromium and about 3V^ per cent nickel. 
The difference in properties between these two classes is not fully revealed bj' a 
comparison of the results of tension tests. Though either high or low ohro- 
mium-nickel steel can be treated to produce nearly the same tension test 
results, the high chromium-nickel steel is much superior in shock resistance 
and endurance. In addition to these two classes, there are intermediate 
types. 

The carbon content of these steels varies with the purposes for which they 
are to be used. With less than about 0.25 per cent carbon, they are used 
principally for case hardened pieces such as cam rollers, push rods, pivots, 
axles, crank shafts, gears, and any other parts requiring a combination of 
hardness and strength inith toughness. High chromium-nickel steel, with 
0.25 to 0.45 per cent carbon, is used for armor plate. 

Vanadium Steel. With the exception of carbon, possibly no element has 
a greater e£fect on the physical properties of steel than has vanadium. Whezx 
added in such quantity that 0.10 to 0.20 per cent remains in the finished metal, 
the tensile strength and elastic limit of the steel are greatly increased with 
little or no decrease in the ductility. The dynamic properties also are 
greatly improved. 

A great part of this improvement in properties is probably due to the scav- 
enging effect of vanadium. On account of its great affinity for oxygen, 
vanadium removes most of the residual oxygen after the usual deoxidizing 
agents have exerted their full effect. Since vanadium has an affinity for 
nitrogen, it is probable that it removes some of this element also, with conse- 
quent improvement in physical properties. 

In addition to the improvement due to the scavenging effect of vanadium, 
there is probably also an improvement due to the effect of the vanadium 
remaining in the steel. Except in high speed steels, however, there seems to 
be no advantage, and there may even be a disadvantage, in the presence of 
more than about 0.3 per cent vanadium. Vanadium in steel occurs partly 
in the form of double carbides, which strengthen the steel, and partly in the 
form of a solid solution in the ferrite, which toughens the steel. 

Chromium-Tanadium Steels. Vanadiiun seems to exert its best effect 
in steel when in conjunction with chromium or nickel. In the former oombia' 
nation it seems to be most useful ; most commercial vanadium steels contain 
chromium. Clut>mium*vanadium steels rival chromium-nickel steels' in 
their usefulness in structural or machinery parts which require strength and 
fatigue resistance. With a carbon percentage of less than about 0.25, 



CHEMICAL COMPOSITION—PHYSICAL PROPERTIES 107 

chromium-vanadiuixi steel is used chiefly in parts that are to be case hardened. 
With a carbon percentage of 0.25 to 0.40, this steel is used in quenched and 
tempered machinery parts, such as axles, crank shafts, connecting rods, etc. 
With a percentage of 0.45 to 0.65, it is used for springs. 

Chromium-vanadium steel is much, softer than chromium-nickel steel. 
It is more easfly forged and machined. Like chromium-nickel steel, its full 
value is deA^loped only by quenghing and tempering. For effective treat- 
ment of this kind, however, it must be quenched from a higher temperature 
than is used in the treatment of chromium-nickel steel. The physical prop- 
erties obtainable in the heat treatment of chromium- vanadium steel fall 
off very rapidly with increase in the size of the object treated. In large 
objects, the properties obtainable are Inferior to those obtainable with 
ohromium-nickel steel. 

Molybdenum. This element occurs partly in solid solution in the ferrite, 
but chiefly in the form of double carbides in the cementite. In its effect 
on the physical properties it is similar in some respects to chromium and 
tungsten. On account of its lower atomic weight molybdenum can replace 
two or three times its weight of tungsten. Molybdenum is said to have a 
better effect than chromium on the ductility, toughness, and dynamic strength 
of steel. Excellent physical properties have been obtained in properly treated 
molybdenum steels. These steels have been used for rifle barrels, large 
guns, for machine parts such as propeller shafts, and to replace the tungsten 
of magnet and tool steels. The use of molybdenum in steel is rapidly 
inereasing. 

Chromilim- molybdenum steels have recently been used in automobile 
parts requiring fatigue resistance. Nickel-molybdenum steels have also 
recently been used, but are said to be inferior to chromium-molybdenum 
Bteels. 

Tungsten. like molybdenum and chromium, this element occurs partly 
in solid solution in the fenite of steel; it also occurs in the form of double 
earbides in the cementite, and probably in the form of iron-tungsten com- 
pounds. Though it retards the rate of transition from austenite to pearlite, 
its influence in this respect is less than that of chromium. In small per- 
oentages, tungsten increases the strength of steel with only slight increase 
in brittleness. For this reason, about 0.6 per cent tungsten is sometimes 
used in springs. 

Magnets made of water quenched tungsten steel retain their magnetism 
better than carbon steels. Steel of the following percentage composition 
gives the best results: carbon, 0.5 to 0.7; tungsten, 4 to 7. Sometimes 
0^ per cent of chromium is added, and sometimes molybdenum is used in 
place of tungsten. These steels should be quenched from about 800 to 850 
deg. C. 

Self Hardening Tool Steels. The original air hardening pr "Mushet" 
tteel contained 4 to 12 per cent tungsten, 2 ^o 4 per cent manganese, and 
1.5 to 2.5 per cent carbon. The self hardening properties of this steel 
were due more to the manganese than to the tungsten. Tungsten, even 
in high percentages and in the presence of carbon, confers very little self 
burdening properties on steel. Since the high percentage of manganese in 
this Mushet steel caused brittleness and tendency toward quenching cracks, 
the manganese was soon replaced by chromium, which confers self hardening 
properties with less brittleness. Becker gives the following range of com- 
posdtion of self hardening steels: carbon, 1.1 to 2.4 per cent; tungsten, 4.5 



108 IRON AND 8TBEL 

to 11.6 per cent; chromium, 0.07 to 3.4 per cent. The tungsten may be 
replaced by molybdenimi. 

Hiffh 8p««d Steel. Tools of self hardening steel, even if they contain 
considerable chromium and tungsten, have little if any better cutting speed 
than tools of carbon steel. If, however, such steels are heated to 1200 to 1350 
deg. C. and cooled rapidly, they acquire the property of "red hardness. " 
A tool made of this steel, when cutting 8Q rapidly that the point is heated to 
dull redness, will not only retain its cutting edge but will be even harder than 
it was before use. 

A study of the microstructure of the steel explains in part the remarkable 
properties produced by the high temperature heat treatment. At the high 
temperature, the double oarbides of iron-tungsten compounds dissolve and 
form an austenitio structure. This structure, preserved in the steel by rapid 
cooling, is so stable that, when heated to 600 deg. C, the transformation 
proceeds only as far as martensite. The red hardness of high speed steel is, 
therefore, due to the stability of the martensitic structure even at dull redness. 

The stability of the martensite at dull redness is due principally to the 
tungsten, while the hardness and self hardening properties are due principally 
to the chromium. Taylor and White, the discoverers of high speed steel, 
made many experiments to determine the best percentages of carbon, chro- 
mium and tungsten for these steels. They found that improvement could 
be made by decreasing the percentage of carbon and increasing the percent- 
ages of chromium and tungsten. The following percentage composition 
gave the best results: carbon, 0.674 to 0.682; chromium, 5.47 to 5.95; 
tungsten, 17.81 to 18.19. 

Since the discovery of high speed steel many other elements have been 
tried. Many of the modern high speed steels are very complex; they may 
contain, in addition to chromium and tungsten, one or more of the followini^ 
elements: uranium, sirconium, cobalt and vanadium. Of these recently tried 
elements, however, vandium is the only one that has proved of unquestioned 
advantage. Though this element is used in quantities as great as 3 per cent, 
about 1 -per cent api)ears to produce the best effect on the cutting properties. 

SUroonium. In addition to its use in high speed steel, sirconium has been 
used in bullet proof thin steel plate. For this use, a xiicke!*Blrconiuir& 
Steel was found superior to either chromium-nickel or molybdenum-nickel , 
steel. The steel had the following percentage composition: carbon, 0.42; 
manganese, 1.0; silicon, 1.5; nickel, 3.0; zirconium, 0.34. 

Titanium. This element, on account of its strong affinity for oxygen, 
is a valuable deozidisinif agent in steel manufacture. By eliminating 
oxides to a greater extent than usual, titanium tends to prevent the formation 
of blow holes. The delayed solidification of the metal, due to its freedom 
from oxides and to the great heat of formation of titanium oxide, tends also 
to diminish the "pipe." Titanium has also a strong affinity for nitrogen, 
forming red crystals of titanium nitride. 

Although titanium does not remain in the finished metal, the increased 
soundness and freedom from oxygen and nitrogen, produced by its use, greatly 
improves the physical properties. 

Copper. It was formerly believed that copper, even in small percentages, 
produces red shortness in steel. Careful investigation, however, has shown 
that this element in percentages under about 1.5 does not produce red shorts 
ness, unless there is also present a rather high percentage of sulphur. Copper, 
in quantities up to about 1 per cent, produces a slight increase in tensile 
strength and elastic limit, with little if any decrease in ductility. 



CASS CARBURlZJiTlON 



109 



Coppttr has raoently been lued in steel plate to dlmlnJah corrosion. 
For this piupoee it is used in percentages up to about 0.5. In the presence 
of this element, the rust film, instead of accelerating corrosion, is protective. 

Case Carburisation or Partial Cementation 

Of the many investigations of this subject, the most valuable are those 
by QioltUi and his co-workers. These physico-chemical and metallog- 
raphie investigations, especially of the action of gaseous carburiaing agents, 
have thrown much light on the entire subject of cementation of iron and steel. 

Giolitti found that, in the absence of penetrating gases, carbon, even when 
finely divided and in close contact with iron, exerts a carburiaing action so 
slight as to be commercially negligible. 

In most solid cements, the carburiaing action li duo largely to the 
specific. action of carbon monoxide or gaseous hydrocarbons generated from 
the cement. 

The carburiaing action of carbon monoxide is due to a reaction expressed 
by the following equation: 2 COt^COs -h C. This reaction, being reversi- 
ble in the presence of a catalyier such as iron, proceeds to an equilibrium, 
in which the relative concentrations of the two gases depend only on the 
temperature. If the concentration of carbon monoxide exceeds this defi- 
nite relative value, the reaction as indicated by the above equation, sets free 
carbon. Since carbon monoxide penertrates red hot iron, the carbon set 
free by the above reaction is deposited in the interior of the metal, the con- 
centration decreasing with depth. If the temperature of the metal is above 
the transition range, this carbon dissolves in the austenite. 




0w6 1 1.5 2 2.5 3 
llillaeton 

Fro. 6. 



OX 1 IJ 2 2.5 3 
Mlllmeten 

Fio. 7. 



OjB 1 1.5 2 2.5 8 
MiUmetefs 

Fio. 8. 



Aooording to Giolitti, the eoncentration-depth curve obtained with carbon 
monoadde is of the form shown in Fig. 6. The curve shows the effect of 
paasing carbon monoxide for 10 hours over iron at a temperature of 1100 
deg. C. With increase of temperature, pressure or time of exposure, the 
depth of penetration increases; the maximum concentration, however, de- 
creases with rise of temperature. When carbon monoxide alone is used, 
the maximum concentration never reaches the eutectoid value, and the de- 
creaae of concentration with depth is gradual. This form of cArve was 
designated by Giolitti as Type I. 

Though gaseous hydrocarbons, such as methane or ethylene, deposit carbon 
on the surface of the iron, their chief cementing action is due to their penetra- 
tion of iron and liberation of carbon in the interior. Gaseous hydrocarbons 
give conoentration-depth curves designated by Giolitti as Type II. Fig. 
7 shows the effect of passing ethylene gas for five hours over iron at a tern- 



110 IRON AND STEEL 

persture of 1000 deg. C. Tho maximum carbon oonoentration is much sreater, 
and the decrease of concentration with depth ia much more rapid, than in 
oases of Type I. When slowly cooled, the case consists of an exterior hyper- 
eutectoid layer, an adjacent eutectoid layer, and an inner hypo-eutectoid 
layer. 

When cases of Type II are slowly cooled from the carburizing temperature, 
the eutectoid layer is relatively broad, and the change in carbon content 
between this layer and either the exterior layer or the core is veiy abrupt. 
This is shown not only by the microscope but also by concentration-depth 
ciures such as the one shown in Fig. 8. This curve was obtained frpm a piece 
of steel that had been subjected to the action of ethylene for four hours at 1050 
deg. C. and allowed to cool very slowly. During the slow cooling, the cemen- 
tite and ferrite separating out near the outer and inner boundaries of the car- 
buriccd region attract cementite and ferrite respectively from the adjacent 
regions. This migration of the cementite and ferrite toward* the exterion 
and interior respectively is known as "liquation." 

Carburised cases of Type II, on account of the free cementite in the ex- 
ternal layer, are excessively hard and brittle. On account of this brittleness 
and the sudden decrease of carbon content with depth, there may be scaling 
or "exfoliation" of the case. Exfoliation is especially likely to occur 
when there are distinct layers due to liquation. The cleavage in such 
material when hardened is usually 'at the boundary between the eutectoid 
and hypo-eutectoid layers, since, this is the boundary between hardened and 
unhardened metal. 

Since these disadvantages result from the use of hydrocarbons alone, and 
since by use of carbon monoxide alone the resulting maximum carbon 
concentration is too small for practical purposes, commercial use is made of 
mixtures of carbon monoxide and hydrocarbons in the proper proportions 
to produce cases of any intermediate type. By this means the maximum 
carbon concentration may be so regulated that it does not exceed the eutec- 
toid value. 

Another method of obtaining cases of intermediate type consists in the use 
of carbon monoxide in the presence of excess carbon. The metal, surrounded 
by finely divided charcoal, is subjected to the action of carbon monoxide. 
If the temperature is sufficiently high, or the action long continued, this 
method may even produce hyper-eutectoid layers. By regulation of the 
temperature and the concentration of the carbon monoxide, however, it 
is possible to obtain eases of intermediate type. Practical regulation of the 
concentration of the carbon monoxide may be secured by the use of producer 
gas of properly adjusted composition. 

Cases of Type II may be converted into cases of intermediate type by the 
use of carbon monoxide alone. The carbon monoxide thus exerte an equaliz- 
ing action, reducing the carbon content in the external layer and flattening 
the carbon concentration gradient. 

Most solid carburising mixtures owe their oarburising action to the evolu- 
tion of carbon monoxide or a mixture of carbon monoxide and hydrocarbons in 
the presence of excess carbon. The carburising action of leather residues 
and other cements of animal origin is due, not to the formation of cyanides 
as formerly supposed, but to the evolution of gaseous hydrocarbons. One 
of the best known solid cements oonaiste of a mixture of 60 parts charcoal 
and 40 parte barium carbonate. This mixture forms carbon monoxide by 
the action of the carbon on the carbon dioxide evolved from the carbonate. 
The mixture after use regains ite value by absorption of carbon dioxide from 
the air. 



CAST IRO\ 111 

Although the effect of cyanides in solid earboDaoeoUB eemente is alight, 
eyanides and ferro- and ferri-cyanides of the alkali metals have a very rapid 
carburiaing action. They are used to produce quickly a thin, ht&rd case 
in which the carbon concentration decreases ranidly with depth. For this 
purpose, the metal is either immersed in a vessel of molten cyanide until the 
required carbuxisation is obtained, or dipped in the cyanide and afterward 
heated to redness in the air. From five to fifteen minutes' immenion is 
reqmzed to give the desired effect. 

Heat Treatment After Carburlsfttioii. "Since the object of case 
hardening is to produce a hard surface, the carburized pieces are usually 
quenched in water or oil. Frequently, however, they are allowed to cool 
dowly after carburization, |tnd then reheated and quenched. Since, as 
Illustrated by Fig. 8, the preliminary slow cooling may cause liquation and 
consequent exfoliation, it is better to quench the metal from the temperature 
of carburization. On account of the long heating during carburization, 
and consequent coarsening of the structure of the core, however, it is usually 
necessary to give additional heat treatment for grain refining, Since, on 
account of the higher carbon content of the case, the grain refining tempera- 
ture of the case is usually lower than for the core, it is usually necessary 
to give two heat treatments to case carburized steel. The first or ''re- 
generatiTie'* heat treatment consists in heating to a temperature slightly 
above the transition range of the core and quenching; this refines the core. 
The second or hardening treatment consists in heating to a temperature 
shgfatly above the transition temperature of the case and quenching; this refines 
and hardens the case. Although these two treatments are usually necessary to 
produce the best properties in core and case, one treatment may be sufficient 
if somewhat inferior properties in either case or core are unobjectionable. 

CAST IRON 

Foundry "Pig Iron. Iron castings are made by remelting the blast furnace 
product known as "foundry pig iron." Foimdry iron was formerly graded 
entirely by the appearance after fractiue. The grades were numbered in 
order of decreasing coarseness of fracture from No. 1 to No. 6. In the series 
thus obtained, the color varies in the same order as the coarseness. In 
Nos. 1 to 4, the fracture is gray; in No. 5, usually called "mottled" iron, 
the fracture shows alternate patches of white and gray; No. 6, from the color 
of its fracture is known as "white" iron. 

Thoui^ flprading by fracture is still in use, increasing use is now being made 
of chemical analjrsis. In some specifications, while the system of grading 
hy numbers is still retained, a range of chemical composition is prescribed for 
each grade. While there are great differences between the various speci- 
fications in the range of composition assigned to the different grades, the 
average ranges are approximately those given in Navy Department speci- 
fications for foiuidry pig iron, p. 148. In some specifications, such as those of 
the A. S. T. M., grading by numbers has been abandoned. 

The differences in properties between the grades of foundry pig iron are 
due chiefly to variation in condition of the carbon. While the variation in 
total carbon content b relatively slight, the variation in the condition in 
which the carbon occurs is great. In No. 1 foundry iron, the carbon occurs 
almost entirely in the form of graphite. In white iron, it occurs entirely in 
the form of "combined carbon." In the various intermediate grades, the 
graphite and combined carbon occur in various proportions. The con- 
dition of the carbon is influenced largely by the chemical composition, and 
especially by the silicon content. 



112 inON AND STEEL 

» 

lUcroitnieture of Gray Cut Iron. Since the various grades of foundry 
iron and gray cast iron are all transformation products of the auste^ite- 
cementite series, the microstructures of these irons should be studied in con- 
nection with those of the steel-white cast iron series. White cast iron, when 
slowly cooled, consists of the aggregates primaustenoid, euteotic, and some- 
times primary cementite, see p. 85. Since the austenoid, both primary 
and euteotic, consists of pro-euteotoid cementite and pearlite, and since the 
peariite consists of ferrite and cementite, the ultimate structure of white 
cast iron is made up entirely of these two constituents. In gray cast iron, 
however, more or less of the cementite has been decomposed into ferrito 
and graphite. The microstructure of low phosphorus gray cast iron, there- 
fore, consists of ferrite, graphite, and usually cementite in various states of 
aggregation. In foundry irons, there is usually enough phosphorus to 
form an euteotic of iron phosphide, ferrite, and sometimes cementite. This 
eutectic is known as "Stoftdito." 

Although the degree of graphitisation of the cementite is influenced 
chiefly by the. percentage of silicon, it is also greatly influenced by the 
duration of exposure to various temperatiures between the solidifleation tem- 
perature and room temperature. The effect of temperature on graphitiza- 
tion is illustrated by the rapidity of decomposition of the primary cementite 
of hyper-eutectic cast iron. This primary cementite, which is formed at a 
temperature above that of final soldification of the iron, is often decomposed 
immediately after formation, the graphite thus formed floating on the surface 
of the molten iron as a scum known as "kish." In solidified iron, gra- 
phitization, though less rapid than in molten hyi^er-eutectic iron, may 
proceed rapidly if the iron is held near the temperature of final solidification. 
From this point, the rate of graphitization decreases rapidly as the tem- 
perature is lowered. The degree of graphitization, therefore, depends on 
the rate of cooling after solidification, and this in turn depends on the size 
of the casting. 

If cast iron, having a sufficient percentage o( silicon, is held at a tem- 
perature just below that of solidification, or is cooled at a slow enough rate, 
the eutectic cementite is decomposed, leaving a matrix consisting essentially 
of hyper-eutectoid steel. If the percentage of silicon is still higher, or the 
rate of c^x>ling is still lower, there may be also a decomposition of the pro- 
eutectoid cementite, leaving a matrix of eutectoid steel. With still further 
increase in the i^ercentage of silicon, or decrease in the rate of cooling, there 
qiay be partial or complete decomposition of the cementite of the pearlite, 
leaving a matrix of hypo-eutectoid steel or even of nearly, pure ferrite. 

The degree of graphitization depends also on the pouring temperattire; 
the higher the pouring temperature, the less the decomposition of the cement- 
ite. For this effect of pouring temperature, no conclusive explanation has 
been given. 

Properties of Cast Iron in Relation to BUcrostnicture. Since gray 
cast iron consists of a matrix, varying from white cast iron to nearly pure 
ferrite, in which are embedded particles of graphite of various sizes and 
shapes, the physical properties may evidently vary over a wide range. These 
properties depend on the microstructure of the matrix and also on the amount 
and distribution of the graphite. Since the graphite particles break up the 
continuity of the matrix, they exert a weakening effect depending on their 
number, size and shape. The softest and weakest cast iron is that having 
a ferrite matrix and having the carbon all in the form of graphite. With 
increase in the amount of pearlite, the matrix increases in strength; the 



CA,3T XHON 



113 



a 



I' 



Total 
Cftrboii, 



Mo.< 
Ho.3 

Gray forfe 



Mottled 
Pig Iroa 



.IJ. 



WbU« Fij ITOU 
Ultra yhU> Cart fi 



SP^uDJ 



tttcol 



Oa:<t Ifom 



aeoompanying decrease In the quantity of graphite also adds to the strength 
of the metal. Th* ttroncMt iron is one having a pearlitic matrix and 
having the excess carbon all in the form of graphite. Further decrease in 
the quantity of graphite does 
not improve the physical proper- 
ties of the metal, sinoe it merely 
zeplaoes graphite by brittle 
plates of cementite. . 

The relations between the 
percentages of total carbon, oom- 
hined carbon, and graphite in 
the foundry irons and in the 
various types of iron castings 
are illustrated by Figs. 9, 10, 
and II, taken from **The Metal- 
logmphy of Steel and Coat Iron" 
hy Henry M. Hovoe, These dia- 
grams show the relation between 
the gray irons and the steel- white ittntni ^ 8 
cast iron series. Studied in con- J!*!*** £ • *» 

neetion with Figs. 4 and 5, these cact Iran z*"» m m o^% 
diagrams also show thd approxi- *•'*•• 5|"5?'33 g 
mate proportions of the micro- Mft-^H^^S ^ 

constituents and the approxi- Fiq. 9. 

mate properties of> the matrix 
of each ^rpe of foundry ir^n and gray iron casting. 

In these diagrams, the approximate ranges of composition of the various 
foundry irons and types of cast- 
IngB are represented by areas, 
nrhoee boundary lines should be 
considered merely as approxima- 
tions; in fact, the fields should 
overiap. Although the steels, 
smee they have no graphite con- 
tent, should be represented by 
positions on the lines designated 
OA, their names are written be- 
low the line OA in each of these 
figures in order to avoid confu- 
Bon. 

In Fig. 10, the abscissas and 
ordinates of the position desig- 
nated by the name of each grade 
of pig iron, represent respectively 
the approximate percentages of 
eementitlc carbon and graphite. 
%nilariy in Fig. 11, each of the 
areas, 1 to 8, represents the ap- 
proximate range of combined Fio. 10. 
carbon and graphite in a type of 

cast iron; the matrix of each of these tsrpes of cast iron is similar in micro- 
structure to the type of steel represented in the diagram by an equal 



Combined 
Carboo.^ 
P«rc«ut 

Staol 
Wbifo- 




BtMl 



Z 



OMt Iron 



»l 



Cart-lroD«ta • _ _ © "^ 



5a<hmIa! ^ 



8 



114 



IRON AND STEEL 



Chemloal Gomposition and Its Influence on Propertimi 

Silicon. The ordinary range of this element in coke pig iron is from 
about 0.75 to 4 per cent. Pig irons having more than 4 per cent, however, 
are frequently ujsed as a means of adjusting the percentage of silicon in 
mixtures for casting. Irons having from 3 to about 6 per cent silioon are 
sometimes called "Scotch'' irons; those having about 6 to 14 per cent are 
known as "silvery"' irons or "softeners." If more tlian about 14 per 
cent is present, the alloy is called ferro-silicon. Although charcoal pig 
iron may have from 0.1 to 5 per cent silicon, iron having from 0.1 to 0.75 
per cent is most useful. Since coke pig iron having less than about 0.75 

4.0 r 



8.0 



8 

o 

u 
«) 

^-2.0 

j: 
a 



1.0 



Steve Plato 

Badlatori 

Steam-f Auto 
,*i-^CyllD4lcra 

I . j Obilled 
I CnrwIjctU 



51 



-0 



I I 

Malleable 



Xydraulic 
Cyllodora 




WbtU Iron Oaatingt' 



I i .1 



AJ " ^- 



^ DL 



Comblued .0 Of o.< on tie i.<n.« i.* !■• to a «•* 



OaTbOB. 
Perceni 



CI 



so 



4» 4t 



White. |« SS.5 a 

Caat'Iron f:*; m.S'S • 

Scriei kA '<H« Oi 



t Steel • 

— * 

> 5 



Cast Iron 



Jia. 11. 



per cent silicon is of poor quality, chiefly on account of its high sulphur ooa- 
tent, it cannot compete with charcoal pig iron of this composition. 

Since silicon decreases the solubility of carbon in molten iron, the per- 
centage of total carbon in pig iron decreases with increase in the idlicon per- 
centage. While in coke pig iron of low silicon content, the total carbon is 
nearly 4 per cent, in pig iron containing 4 per cent silicon the total carbon 
percentage is only about 3.2. 

The most important influence of silioon, however, is on the condition 
of the carbon. Differences in silicon content are the chief cause of the 
differences in the proportions of combined and graphitic carbon in the various 
grades of pig iron as illustrated in Fig. 11. The usual silicon percentages 
in such foundry irons are approximately as listed in Navy Department 
Specifications, p. 148. 



CAST IRON 



115 



tn^Qr Mid m^ngamwi, unlike silioon. inoieaae the stability cxf the 
eementite and thus retard graphitiiation. A change of 0.01 per oent in the 
mlphur content has a noticeable effect on the quantity of cemenUte and 
therefore on the hardness of cast iron. Since sulphur in cast iron as in steel 
has an embrittling effect* its percentage is carefully limited by specifications. 
Manganese below about 1 per cent usxially does not have much harden- 
ing effect; it may even have a softening effect due to its affinity for sul- 
pfanr. When the percentage rises above 1, however, the hardening effect is 
considerable. 

Since phcMQ^liorui increases the fluidity of cast iron, its presence is desired 
in eastings of thin section or intricate form, if great strength is not essential. 
Phosphorus, occuning as it does in the form of the biittle eutectic, Steadite, 
increases the brittleness of cast iron. For this reason, castings in which 
strength is essential should contain leas than 0.4 per oent. For ordinary 
castings, the average is about 0.7 per cent. In material such as stove plate, 
and in ornamental work, phosphorus may exceed 1 per cent. 

Oljfgtii. J. S. Johnson, Jr.^ as a result of a large number of experiments* 
formed the opinion that dne of the most beneficial elements in cast iron is 
ozygsn. He states that analysis has shown that the chief reason for the 
superiority of charcoal pig iron, especially cold blast charcoal iron, is the 
presence of oxygen. His theory is that the retention of oxygen in the iron 
is favmed by the low hearth temperature of the charcoal blast furnace. 
By artificially oxyssnating coke iron, Johnson was able to produce pig iron 
superior in strength to cold blast charcoal iron. The superiority of the 
oxygenated irons appears to be due to the fact that the graphite, instead of 
forming in long plates, forms in rounded particles. This spheroidising of 
the graphite would undoubtedly offset the detrimental effect of the oxygen 
on the matrix. Johnson's opinions in regard to the effect of oxygen are not 
shsied by all prominent metallurgists. 



Table 7 




WUte iron castings 

Chilkd cMtings 

Cvwlwels 

Chilled rolls 

MftOesble rastinci. as cast 

CSrfiBders; air, gas, ammonia, 

orsidie 

OoA iron 

Bedplates 

Piston rings 

Automobile cylinders 

Uicluaecy eaetinsB, heavy 

If schinery castings, medium . . . 

Msebinenr castings, light 

Dynsmo frames 

Qiatebars 

Pipe fittings 

Stove plate 

Omsmeatal eastings 



hy- 



0.5 -0.9 
0.6-1.25 
0.6 -0.8 
0.6 -0.85 
0.45-1.25 

1 .0 -1 .75 
1.0 -1.25 
I. 25-1. 75 
1.5-2.0 
1.75-2.0 
1.25-1.75 
1.75-2.0 
2.0 -2.4 
2.0 -2.5 
2.0 -2.25 
2.0 -2.5 
2.25-2.75 
2.5 -3.0 



per cent ^ ^%l'^^ 




0.1-0.25* 
0.06 ' 
0.09 

. 0.06 
0.1 

0.10 
0.05 
0.12 
0.06 
0.06 
0.10 
0.08 
0.06 
0.06 
0.06 
0.08 
0.06 
0.06 



Total 
carfoon, 
I>er oent 



0.8 

0.25 

0.4 

0.4 

0.225 

0.5 

0.3 
0.4-0.6* 

0.5 
0.4-0.5* 

0.8 

0.8 

0.7 

0.6 

0.2 

0.4 
0.8-1.25 
1. 0-1. 25* 



0.8 
0.6 
0.8 
0.8 
0.3 

0.8 
0.4 
0.8 
0.6 
0.8 
1.0 
0.8 
0.6 
0.4 
0.6 
0.6 
0.6 
0.4 



4.00 1 
3.5 -3.75 
3.5 -3.75 
3.0 -3.25 
2.5 -3.5 

3.0 -3.5 

2.75-3.25 

3.25-3.75 

3.25-3.5 

3.0 -3.25 

3.0 -3.25 

3.25-3.5 

3.25-3.75 

3.25-3.5 

3.25-3.5 

3.25-3.75 

3.5 -4.0 

3.75-4.0 



"Limits, 
t Below. 



116 IRON AND STEEL 

iiuzninum and nickel aooelerate, while Tanadium and ohromlttm 

retard graphitisation. In general the effects of theee elements on the matrix 
of cast iron are the same as their effects on steel. 

Castings for Various Purposes. Table 7, taken from ' 'Principles of Iran 
Founding^** by Richard Moldenke, gives the average compositions of castings 
for various purposes. The series, which is arranged approximately in order 
of silicon content, follows the same general order as the series shown in Fig. 1 1 . 

Chilled castings require careful adjustment of the quality and com- 
position of the mixture. Charcoal pig iron, melted in the air furnace, is 
used in chilled castings of high quality such as chilled rolls. For car wheels, 
coke pig iron is now frequently used. The percentages of silicon necessary 
to give various depths of chill are given in the Table 8 taken from* 'Principle* 
of Iron Founding,** hy Moldenke, 

Tables 

Silieon in mixture, per cent |l.20i|.loll.00i0.90 0.85i0.80|o.75i0.65 0.6O|o.SO(0.4O 



Silicon in casting, per cent. . 



0.900.80 



Depth of chill, in H'H H I IM IHIH B4, 2 I 1^ 3 

I 'I'll 



0.70,0.60,0.55 0.5O:0.45jO.35 0.30 0.20 0. 10 



"Qun Iron/' so named from the fact that this type of iron was formerly 
used in cast iron cannon, is gray iron of the highest quality. It is used in 
castings in which strength is essential. Gun iron is usually made in the air 
furnace from the best grades of pig iron and scrap. 

For parts of electrical apparatus, such as dynamo pole pieces, in 
which high magnetic permeability is required, a soft grade of cast iron is 
necessary. For this reason, the combined carbon and manganese should 
be kept low. The percentage of graphite should also be reduced, if possible, 
by addition of steel to the mixture. 

Orowth of Cast Iron at Red Heat. When gray cast iron is heated 
above about 650 deg. C. there is a permanent increase in volume, the amount 
of increase depending on the temperature and length of exposure; the growth 
is especially noticeable after the iron has been repeatedly heated and cooled. 
An increase of about 17 per cent in length and 46 per cent^n volume has 
been observed, with decrease in the specific gravity from about 7.1 to 5}i2- 
Although growth does not occur below 650 deg. C, above this temperature 
the rate of growth increases rapidly and reaches a maximum at about 736 
deg. C. 

It has been found that the growth is roughly proportional to the per> 
centage of silicon, and hence to the percentage of graphite. That the growtli 
is due chiefly to penetration of oxygen to the interior by way of the graphite 
plates is evident from the following facts: Microscopic examination shows 
that the graphite plates in the enlarged iron are surrounded by layers of 
oxides; the weight of the enlarged iron, as well as its dimensions, is con- 
siderably increased; growth does not occiu' if the iron is heated in a vacuum. 
Growth of cast iron after repeated heating, therefore, is due to the increaised 
volume of the oxidised material. 

Since growth by internal oxidation results in impairment of the physical 
properties and final failure of the material, the percentage of graphite itx 
material for grate bars, furnace sections, annealing boxes, etc., should be 
as low as possible. When white cast iron is unsuitable on account of its 
brittleness^ the best cast iron for such purposes is a gray iron whose com-, 
position is near the boundary between gray and mottled iron. Low per-. 



CAST IRON 117 

oentacoB of sulphur and phosphorus also are desirable in such material. 
For this reason, the best pig iron for use in heat resistant castings is of the 
Bessemer grade. 

Shrinkage of Cast Iron. Some writers make a distinction between 
the terms "ahrtnkage" and "oontraetlon." They apply the term 
"shrinkage" to the decrease in volume during solidification, and the term 
"oootraction" to the decrease in volume after solidification. Since, how- 
ever, both words have the same general meaning, and are in common use 
to designate decrease in volume either before or after solidification, a dis- 
tinction between the terms seems inadvisable. 

After solidification of cast iron, in addition to the natural decrease in 
volume with falling temperature there are from one to three volimie jBhanges 
due to transition from one kind of microstructure to another. There may 
be actual expansion of the iron at about 1100, 900, and 725 deg. C. The 
first of these expansions is due to the formation of the relatively bulky 
graphite; the second (in phosphoric irons) is due to the solidification of the 
phoq^hide eutectic; the third is due to the formation of pearlite. The net 
result of the cooling to room temperature, however, is a shrinkage, which 
varies with the composition of the material. 

The shrinkage or contraction in white eait iron is about }i in. per foot. 
In graj irons, the shrinkage depends on percentage of silicoUf sise of cast- 
ing, pouring temperature, etc. In other words, the shrinkage is decreased by 
every factor that increases the percentage of graphite. The average allowance 
for shrinkage in gray cast iron is }^ in. per foot. 

KsUeable Cast Iron. This metal as cast is a white iron. It is after- 
ward so altered by annealing that it greatly exceeds ordinary gray iron in 
strength and ductility. The improvement in properties is due to the fact 
that the malleablising process either removes the carbon almost entirely 
from the white east iron or converts it into scattered groups of fine particles 
known as "temper carbon" which are less harmful than the graphite flakes 
of gray cast iron. 

There are two processes of making malleable cast iron. The original 
Etaumur process, still used in Europe, is chiefly one of oxidation. In 
this process, white iron, packed in iron oxide, is heated for about 110 houra 
at 850 to 950 deg. C. By this method, most of the carbon is removed. The 
resulting metal, since it gives a light colored fracture throughout its entire 
eroBs-section, is known ss "white heart" malleable cast iron. 

The American malleabUaing process is essentially one of graphitisa- 
lion, though it also produces some surface oxidation. In this process, the 
white cast iron is packed in a mixture of one part new ore and two or three 
parts ore that from previous use has lost neariy all its oxidizing power. It 
ii then heated for about 60 hours at about 675 to 730 deg. C. In the re- 
iolting product, the fracture is dark in color with the exception of a de- 
carbonised exterior layer. ' For this reason, the product is called "black 
kssrt" malleable cast iron. 

The difference in form between the graphite of gray and of malleable cast 
in>n is due to the difference in the temperatures at which graphitisation 
r eccurs in the two kinds of material. While the graphitization of gray cast 
hon occurs chiefly at a temperature not more than 30 to 40 degrees C. below 
the temperature of solidification, the graphitization of malleable cast iron 
occurs at a much lower temperature. At the lower temperature, the rigidity 
of the metal hinders the coalescence and growth of the graphite particles and 
thus prevents the formation of graphite fiakes. 



118 IBON AND 8TBEL 

The composition of the iron for malleable caetingiB mi»t be so adjusted 
that no graphite forms during the casting process; yet there must be enou^^ 
silicon present to facilitate graphitisation during the annealing process. 
Since sulphur diminishes the strength and increases the tendency to form 
shrinkage cracks, the percentage of this elezfient must be kept low. Since 
phosphorus diminishes the shock resisting power, the percentage should not 
exceed about 0.25 per cent. The average compositioa of malleable cast iron 
is given in Table 7 above. 

The itrength of east iron in relation to the various typcB of micro- 
structure has already been discussed. Description of the tests and the 
usual niimerical values representing the strength of the different kinds of 
cast iron are given in the specifications, p. 149. The tensile ttrmiftii 
does not usually much exceed 20,000 lbs. per sq. in. unless considerable steel 
scrap has been used in the mixture. The tension test is of less value than 
the cross breaking or "transverse" test. For this test, square or round 
bars of various cross-sections and lengths are in use. The " arbitration bar*' 
of the American Society for Testing Materials, however, is in general use. 
This is a cylindrical bar 1^ in. in diameter, which is tested on supports 12 
in. apart; see pp. 150 and 152. The eompreBSive itreniftli of cast iron is Ob 
most valuable property. It varies from 60,000 to 200,000 lbs. per sq. in. 

Meltlnflr Processag for Catt Iron. Cast iron is usually melted in either 
the cupola or the "air furnace." The crucible, open hearth, or electric 
furnaces are sometimes used. 

The eupola is a shaft furnace, usually at least 15 ft. high and 2}>ito7}><2 
ft. in diameter, consisting of a vertical cylinder of boiler plate lined with 
fire brick. The top is open for the escape of the products of combustion, and 
near the top is a side opening to receive the alternate charges of fuel and 
metal. At the bottom is the hearth or crucible with tap holes for slag and 
metal. A little above the slag hole are the tuyeres for air blast. 

In charging the cupola, coke Is added first until the coke bed extends 
about 22 to 24 in. above the tuyeres. Alternate charges of metal and fuel 
are then added until the cupola is full. Each fuel charge except the first 
should be in sufiicient quantity to make a layer about four inches deep. 
Each metal charge will ordinarily weigh about ten times as much as a fuel 
charge; if the metal charge contains considerable steel, however, the charge 
must be smaller, and may be only seven times as much as the coke charge. 
In adding the metal charge, any steel in the mijcture should bo added first, 
so that it will be in direct contact with the preoedeing fuel charge; a layer 
of pig iron is then added, and finally a layer of light cast iron scrap. Charged 
in this order, the three kinds of material will melt almost simultaneously. 

After the charged cupola has remained for an hour or two with air blast 
nearly shut off, the full blast is turned on. The "first metal" should appear 
in the hearth in eight to ten minutes; if less time is required, the first fuel 
charge has been too thin. The melting may be allowed to continue without 
addition of further charge until the cupola is empty, or the charging may be 
continuous as in a blast furnace. 

There are two types of air furnace. Both t^'pes are reverberate ry furn- 
aces. The first type is used in gray iron foundries for making the best grade 
of castings such as chilled and sand rolls, steam and gas engine cylinders, 
gim iron, etc. This furnace, being fairly high and wide in proportion to its 
length, can be charged with heavy scrap. The furnaces vary in capacity 
from 5 to 40 tons, 25 tons being the ordinary capacity. Natural draft is used. 



FBRRO-ALLOYS 119 

The second typ^ of air furnace is used in making malleable castings. 
Sboe no larger pieces than pig iron are charged, this furnace is made long 
and narrow with a low roof. Forced draft is used. 

Since the metal in the air furnace is not in direct contact with the fuel, 
the sulphur absorbed is less in the air furnace than in the cupola. While 
the total carbon content can be readily reduced in the air furnace by the 
addition of steel scrap, such reduction cannot readily be made in the cupola 
on account of the absorption of carbon from the fuel. In the air furnace, a 
final adjustment of the composition of the metal can be made just before 
tapping. 

Mixture Making for CMt Iron. In making mixtures for iron castings, 
aUowance must be made for changes in composition during melting. These 
changes depend on the type of melting furnace, the quality of the fuel, and 
the care exercised in the melting process. 

The percentaiT® of silicon should be about 0.25 higher in the mixture 
than in the casting, if the cupola process is used. If the air furnace process 
is to be used, the allowance for loss should be 0.35 per cent. 

The losses of manganese in the cupola and air furnace processes average 
15 and 35 per oent respectively of the quantity of manganese in the mixture. 

The loss of carbon in the air furnace is from 5 to 15 per oent of the quantity 
in the mixture. In the cupola, the change is variable.- The absorption of 
carbon from the fuel is greater the lower the percentage of silicon, and the 
larger the percentage of steel scrap in the mixture. 

Id cupola practice, the increase of sulphur during melting is from 
0«02 to 0.07 per cent. In the air furnace, the increase should not be more 
than about 0.01 per oent. 

Since the percentage of sulphur in cast iron is increased by each remelting, 
the proportion of scrap in foundry mixtures must be carefully limited. 
If a large proportion of scrap is regularly used, there will be a progressive 
increase in the 6:iilphur content of the foundry product. 



FSBBO- ALLOTS 

With the exception of ferro-manganese, spiegeleisen, and ferro-silicons 
with lower silicon content, all ferro-alloys are made in the electric furnace. 
A list of the more imi>ortant ferro-alloys, with the approximate percentage of 
each; is given in Table 9. 



IRON AND STEEL 





it 




?= 






n 


ii= 




11 


d do dd 




Ml 


*l;Hs:llSnip I 




ifl 


dl~°r°° 


BR :ae ^o 


IS 


ddadddde 


I'iP '* 


 




,,2^!RSSa2 


dd do « 


J! 


i 




N:Si=i§li 


i 




Ll 







WROUGHT IRON SPECIFICATIONS 



121 



BPBCIFIOATXON8 FOB WaOUOHT ULON 

U. S. Havy 8p«eUleatloiii (Adopted, 1918) for Wrouffht Iron for chain and mis- 
celUneoua purpoaea require material to be of best quality American refined iron, puddled 
from allHkre pis iron and free from any admixture of steel or scrap. Short pieces must 
not be used in poling. All material shall be free from injurious defects and have clear 
siirfaoea aqd workmaaKfce finish, bars to be straight and of true section. Grade A, 
which muBt be double refined and is specified for chain cable and similar articles, and 
Grade B, which is specified for general blacksmith work, are specified with physical and 
chemical requirements in aeocwdanoe with Table 10. 

Table 10 





Minimum 

tensile 

strength 

per sq. in. 


Minimum 
yield point 


Minimum 
elonga- 
tion 1 


Minimum 

contra<^ 

tion 

area 

<■■■■■■   

Per cent 
40 

40 rounds 
35 flats 


Maximum amount 
of 


Grade 


P 


8 




Per cent 


Per cent 
0.10 

0.15 


Per cent 


A 
B 


48.000 
4&.000 


H ultimate 
strength 

H ultimate 
strength 


26 
25 


0.015 
0.020 



Bends 



Cirade 



A 
H 



Cold 



Quench 



100 deg. around a diam. of one 
thiekni 



Flats H ii^- and less around a 
diam. to two thicknesses, all 
other material to 180 deg. 
around a diam. of one thiok- 
nees. 



Heat to 1700 deg. F< and bend 
to same requirements as cold 
bends. 

, Temperature of the water in 
which the bar is to be 
quenched should he about 
80 deg. F. 



>Th« eloni^tion will be measured in 8 in. with the following exceptions: Flats H in* 
~ leas in thickncas will be measured on a length equal.to 25 times the thickness of the 
itOTs^ tested. 

On all other material less than ^ in. diam. or thickness, the elongation will be meas- 
nred on a length equal to 10 times the diam. or thickness of the material tested. 



Mftterial will be teeted in aises rotted where iM«etieable, and for each ton or 
le» of each aise the following tests will be made: 1 tensile, 1 cold bend, 1 quench bend, 
1 nkk teat, aiad 1 drift test. Eaeh test specimen shall be taken from a different bar. 
When matorial ean not b* tested in sises rolled, test pieose will be prepared to a sectional 
aiea as large as poasible within the eapacity of the testing machine for tensile tests, and 
machined to suitable sise for bending and other i^ysieal teats. For material of sectional 
•raa above 4 sq. in., a reduction of 1 unit of percentage in elongation and contraction, and 
a vedoction of 800 lbs. in tensile strength will be allowed for each additional 2 sq. in., and 
a proportionate amoimt of reduction for fnotSootf iMrta .thereof, provided the ultimate 
qtreagth shall not fall mora than 3000 lbs., nor the elongation more than 3 units of per- 
eentage, below the requirements of the grade of iron tested. 

A bar nieked approximately 20 piTr cent of its thickness and bent back at this point 
throogh an angle of 180 dec., mwt show a long* ekan, silky fiber, free from dag or dirt. 



114 



TRON AND STEEL 



Chemical Composition and Iti Influ«nc« on Propertimi 

Silicon. The ordinary range of this element in eoke pig iron is from 
about 0.75 to 4 per cent. Pig irons having more than 4 per oent, however, 
are frequently used as a means of adjusting the percentage of silioon in 
mixtures for casting. Irons having from 3 to about 6 per oent silioon are 
sometimes called "Scotch" irons; those having about 6 to 14 per oent are 
known as "silTery"' irons or "softeners." If more than about 14 per 
oent is present, the alloy is called ferro- silicon. Although oharooal pig 
iron may have from 0.1 to 5 per cent sOicon, iron having from 0.1 to 0.75 
per cent is most useful. Since coke pig iron having leas than about 0.75 

or 



Stove Plat* 

Radiacort 

Steam-fAato 
._,CyliDdcra 




CojnblDcd 
CarboD. 

Parcent a 

8U«1 .^ 

Whita* «;« 9 5^ a 

Caal'lron £lg m-!: a S 

Serlea »Q ^HM «« 



FlO. 11. 



per cent silicon is of poor quality, chiefly on account of its high sulphur con- 
tent, it cannot compete with charcoal pig iron of this composition. 

Since silicon decreases the solubility of carbon in molten iron, the per- 
centage of total carbon in pig iron decreases with increase in the silioon per- 
centage. While in coke pig iron of low silicon content, the total carbon is 
nearly 4 per cent, in pig iron containing 4 per cent silicon the total carbon 
percentage is only about 3.2. 

The most important influence of sUioon, however, is on the condition 
of the carbon. Differences in silioon content are the chief cause of the 
differences in the proportions of combined and graphitic carbon in the various 
grades of pig iron as illustrated in Fig. 11. The usual silioon percentages 
in such foundry irons are approximately as listed in Navy Department 
Spedfioations, p. 148. 



CAST IRON 



115 



Sulphur and mangMitie, unlike silicon, inoieaw the stability of the 
eementite and thus retard graphitization. A change of 0.01 per cent in the 
milphur content haa a noticeable effect on the quantity of oementite and 
therafore on the hardness of cast iron. Since sulphur in cast iron as in steel 
has an embrittling effect, its percentage is carefully limited by specifications. 
Manganese below about 1 per cent usually does not have much harden- 
ing effect; it may even have a softening effect due to its affinity for sul- 
phur. When the percentage rises above 1, however* the hardening effect is 
considerable. 

Since phogphoniB increases the fluidity of cast iron, its presence is desired 
in eastings of thin section or intricate form, if great strength is not essential. 
Phosphorus, occuning as it does in the form of the biittle eutectic, Steadite, 
increases the brittleness of cast iron. For this reason, castings in which 
strength is essential should contain less than 0.4 per cent. For ordinary 
castings, the average is about 0.7 per cent. In material such as stove plate, 
and in ornamental work, phosphorus may exceed 1 per cent. 

QUfWi. /. B. Johnton, Jr., as a result of a large number of experiments* 
formed the opinion that dne of the most beneficial elements in cast iron is 
oxygen. He states that analysis has shown that the chief reason for the 
superiority of charcoal pig iron, especially cold blast charcoal iron, is the 
presence of oxygon. His theory is that the retention of oxygen in the iron 
is favMed by the low hearth temperature of the charcoal blast furnace. 
By artificially ozyesnating coke iron, Johnson was able to produce pig iron 
superior in strength to cold blast charcoal iron. The superiority of the 
oxygenated irons appears to be due to the fact that the graphite, instead of 
forming in long plates, forms in rounded particles. This spheroidising of 
the graphite would undoubtedly offset the detrimental effect of the oxygen 
on the matrix. Johnson's opinions in regard to the effect of oxygen are not 
shared by all prominent metallurgists. 



Table 7 



Silicon. I ^^P^"'- i p^o?Ss. 
per cent ^^ ^^^ 



Whiie iron eastings 

Chilled castings 

Car wheels 

ChiUed rolls 

llaOeable castings, as cast 

Cylinders ; air, gaa, ammonia, by 

draulie 

Gun iron 

Bedplates 

Piston rings 

Automobile cylinders 

MaehiDery castings, heavy 

Machinery castings, medium 

Machinerv castings, light 

Dynamo frames 

Grate bars 4 

Pipe fitting 

8tove plate 

Ornamental eastings 

•Limits, 
t Below. 



0.5 -«.9 
0.6 -1.25 
0.6 -0.8 
0.6 -0.85 
0.45-1.25 

1.0-1.75 
1.0-1.25 
1.25-1.75 
1.5 -2.0 
1.75-2.0 
1.25-1.75 
1.75-2.0 
2.0 -2.4 
2.0 -2.5 
2.0 -2.25 
2.0 -2.5 
2.25-2.75 
2.5 -3.0 



0.1-0.25* 

0.08 

0.09 
. 0.06 

0.1 

O.tO 
0.05 
0.12 
0.06 
0.06 
0.10 
0.06 
0.06 
0.06 
0.06 
0.06 
0.06 
0.06 



0.6 

0.25 

0.4 

0.4 

0.225 

0.5 

0.3 
0.4-0.6* 

0.5 
0.4-0.5* 

0.6 

0.8 

0.7 

0.6 

0.2 

0.4 
0.6-1.25* 
1.0-1.25* 




Total 
carbon, 
per cent 



0.6 
0.4 
0.6 
0.6 
0.6 
1.0 
0.8 
0.6 
0.4 
0.6 
0.6 
0.6 
0.4 



4.00t 
3.5 -3.75 
3.5 -3.75 
3.0 -3.25 
2.5 -3.5 

3.0 -3.5 

2.75-3.25 

3.25-3.75 

3.25-3.5 

3.0 -3.25 

3.0 -3.25 

3.25-3.5 

3.25-3.75 

3.25-3.5 

3.25-3.5 

3.25-3.75 

3.5 -4.0 

3.75-4.0 



IRON AND STEKL 



li meaaured from the outside at the tabe eEMll 



124 



cracks or flaws. This B&oge ai 
be H in- wide. 

HjrdroatAtio Taata. Tubes uader 6 in. in diam. ahail atand an internal 
hydrostatic preasure of lOOO Iba. per aq. in., and tubea 5 in. in dism. or over 
an int«rnat hydroatatic preaaure of SOO Iba. per eq. in. Ltipwelded tubea 
shall be atruck near both ends, while under pressure, with a 2^1b, hand hammer 
or the equivalent. 

■spkudlnff. Tubee when inaerted in the boiler shall stand expanding and 
beadioK without abowing oraoka or Qawi, or opening at the weld. 

boUh- FutM (ine) 

Umi. Clou A boiler {>late ia auitaUe for use when flanging or welding ia 
not required. CUuaB boiler plate is auitable for use where flangiDg or welding 
is required, boiler manholea, condenser ahells, bafflee and supporting plates, 
feed water heater shells, baffles and plates, blower fans, evaporator shellB, etc. 
Clan C material is suitable for amokestscks, boiler casings, uptakes, etc.. 
where great atreugth ia not required. 

PhTaicftl and ehsinlo*! propertlM shall conform to Table II. 
Tabla 11 









L 


1 










p 


■3^ 


1 




Material 


p 


'J 


1 

i 


j 




k 


¥ 


] 


o 






a 


s 












1 


Eqaal to thlekiuH ef plate and 


^ 


|Op™.i..arth 


l»r 


\^-]- 


0.M5 0.0» 


throu,h.l80d.,.IorpUt»l 

la. ia thiBkneai and und« asd 






175.009 


1 


equal to IH tiinfe tlie thiek- 












neaa through ISO dw. for 
Plata over 1 iq, in cbiduiae. 


B 


[ Open-hoarth 


l«.ooo 


ll")» 


a.tBi o.a» 


Flat back thfoujh ISO dtf. lor 
plain under 1 in. in thieknoa 
and equal to thirkntw of plate 


C 


OpBB-heaith 


will not b« made oa IhiB maleriaT unlns the inapectfirhla reuon 




or Br»e- 




IDHBtwl. 





When the finialied plate ig M in. or leia. the elonntion shall be measured on an eriaiaai 
leosth of IB tinrn the thiclcncn of the plate (eittd. 

number of Teita. One longitudinal tenaito Mat piece and one bending 
teat piece (trsJwverse) shall be cut from each plate aa rolled at such points aa 
may be desiBnated by the inspector. Test piecea for circumferential platen 
of boiler drums shall be pulled in the direction of the circumfereDce. Tho 
cold-bending teat piecea may have their comers ttntnded to a curve, the 
radiua of which is equal to ^ the thickneaa of plate. 

Surface Impectlon. Boiler plates shall be Bat and straight, free of all 
stag, foreign substances, briuJenesH. laminationB. hard spots, brick or scale 
marks, scabs, snakes or other injurious defect*. 



STEEL, U. S. NAVY SPECIFICATIONS 



125 



Traatmant «( B«nt and Tlangad ShMti. Boiler-drum sheets, whenever 
beatt aU fianced sheets, drum heads, headers, nossles, and man and hand hole 
plates which are f<»ined from boiler plate shall be formed hot. All flanged 
parts of boUers will be annealed in an approved manner after flanging. All 
boiler plates and stays will be well oleaned of mill scale by pickling or other 
approved means. ^ 

BoU«r BlTetf, Bods for (1915) 

IFflei. Cla89 A material shall be used for all rivets where class A plate is 
used. Class B material may be used with class B boiler plate. Class C 
material shall be used for rivets where the strength of the boiler is not affected, 
such as: 



Air duets 

Aah dumps 

Aih pans 

Ash-pit doors 

Blower caalnga and fans 

Boiler casing, including that 

tube boilers 
Circulating plates fcM- boilers 
Coal and ash budgets 



for water* 



Fiieroom air screens 
Furnace doors 
Ladders 
Oil tanks 

Smoke pipes and eovera 
Platforms and gratings 
Tallow and other tanks 
Uptakes and uptake doors 
Feed and filter tanks 



Chemical and phyBical requirements must be in accordance with 
Table 12. 

Table IS 



C\maa 


• 

Material 


Min. 
tensile 

lbs. 
per sq. in. 


Min. 
elonga- 
tion, 
per cent 
in 8 in. 

23 
2g 




Max. 
amount of 


Bends* 






P. 


S. 


m 


A 1 Open-hearth nickel or car- 

' bon steel. 

B Open-hei.rth carbon steel. 

C ; Commercial steel. 

i _^ ^ 


75.000 
56.000 


0.04 
0.04 


0.035 
0.035 


CD 
(2) 



* Cc^d bend 180 deg. about an inner diam. equal to \^ the thickness of die test 
piece for diam. «9> to aad including 1 in., and equal the thickness for diam. over 1 in.; 
Quench bend 180 deg. about an inner diam. equal to the thickness of the test piece for 
diam. up to and including 1 in. and equal to 1>^ times the thickness for diam. over 1 in. 

* ObIci beod flat back through 180 deg. : quench bend 180 deg. through an inner 
diam. equal to yi the thickness of the test piece for diam. up to and including 1 in. and 
equal to the thickness for diam. over 1 in. 

* Quench test pieces to be heated to a darlf cherry red, as seen in daylight, and 
plunged into fresh clean water of 80 deg. to 90 deg. F. 

Surface and Other 0eleetf. The rods must be true to form, free from 
seams, hard spots, brittlenees, injurious sand or scale marks, and injurious 
defects generally. 

Upsettinc Teite. From each heat of rounds as rolled there shall be cut 
6 tests specimens about iH ii^- long, which shall stand hammering down cold, 
longitudinally, to H their original length without showing seams or other 
defeets whieh would tend to produce imperfections in the finished product. 

BoUer BlTeti, riniihed (191S) 

Testa. Samples from each lot must stand the following tests without 
fracture, test (a) being applied to. one lot and (&) to a second, etc. : (a) Bend 
double cold to a curve of which the inner diam. is equal to the diam. of the 
riyet; (5) bend double hot through an angle of 180 deg. flat back; (c) 
the head to be flattened when hot without cracking at the edges until its 



126 



IRON AND STEEL 



diam. is 2^ timeB the diam. of the shank; (d) the thftlllai of MU&ple 
rlTett to be nieked on one side and bent oold to show the quality of the 
material. 

3oUer Bracing: (1918) 

Chemical and Physical RaquircmentB must be in accordance with 
Table 13. 

Table 18 



ClftM 


Material 


Min. 

tensile 

strength, 

Ibe. 

per sq. in. 


Min. 

elastic 

limit. 

lbs. 

per sq. in. 


Elongation per 
cent in 




8 m. 1 2 in. 

1 


A 

A 

B 

B 


Shapes, open-hearth steel 

Forgings, open-hearth steel 

Shapes, open-hearth steel 

Forgings, open-hearth steel 


75.000 
75.000 

6aooo 

60,000 


40L000 
4a0Q0 
3ZO0O 
32.000 


23 
23 
26 
26 


26 

26 ' 
30 
30 



Class 



Material 



Maximum 

O! 

P. 



r 



oentage 



S. 



I 



Bending 
tests 



Opening 

and 

closing 

tasU 



A 

A 

B 

B 


Shapes, open-hearth steel 

Forgings. open-hearth steel 

Shapes, opoi-hearth steel 

Forgings, open-hearth steel 


0.04 
0.04 
0.04 
0.04 


0.04 
0.04 
0.04 
0.04 




• 
• 



* See following five paragraphs. ^ 

"A'' Shapes Cold Bend. One test piece cut from each lot of claes A 
shapes for bracing shall bend cold through an angle of 180 deg. to an inner 
diam. eqUai to twice the thickness of the piece tested without showing a 
fracture on outside of bent portion. 

"A" ToTgingB Cold Bend. One bar }4 in. thick, out from each lot of 
class A forgings for bracing, shall bend cold through an angle of 180 deg. to 
an inner diam. of 1 in. without showing a fracture on outside of bent portion. 

"B" Shapes Cold Bend. One test piece cut from each lot of class B 
shapes for bracing shall bend oold through an angle of 180 deg. to an inner 
diam. equal to the thickness of the piece tested without showing a fracture 
on outside of bent portion. 

"B" Forgings Cold Bend. One bar H in. thick, cut from each lot of 
class B forgings for bracing, shall bend oold through an angle of 180 deg. to 
an inner diam. of H ui* without showing a fracture on outside of bent portion. 

Opening and Closing Tests of Shapes. Angles, tee bars, and other 
shapes for boiler bracing shall be subjected to the following additional tests : 
A piece cut from 1 bar in 20 shall be opened out flat while cold without show- 
ing cracks or flaws; a piece cut from another bar in the same lot shall be 
dosed down on itself until the two sides touch without showing cracks or 
flaws. 

Annealing. All forged material for boiler bracing shall be annealed as a 
final process. 

Surface Inspection. All boiler bracing shall be true to form, free from 
seams, hard spots, brittleness, injurious sand, or scale marks, or injurioua 
defects generally. 



STBiL, U. S. NAVY SPECIFICATIONS 



127 



Steel Shapes and Ban for Hull Construction (1917) 

YInisli. All shapes and bars shall be true to section, free from injurious 
defects, and shall have a workmanlike finish. 

Phjsieai and Chemical Requirements. All material shall be of uni- 
form quality. The physical and chemical requirements of the various grades 
of material for shapes and bars shall be in accordance with Table 14. 







Table 14 


« 












Min. 


Max. amount 


. 






Min. 


elongation 


of 






Test 












tensile 


specimens 








Grade 


Material 


strength, 

lbs. per sq. 

m. 








Cold bend 


^»^» m^^M^ 


A V A'^B v^v* acaa 


Type 


'I^ 


P.. 
per cent 


8.. 
per 
cent 


1 








1. per 


and 




1 
1 








cent 


3, per 
















cent 








Soft, for 


Open-hearth 


saooo 


35 


30 


O.QS acids: 


0.05 


180 deg. flat on 
itself 


ll|Yt»gt**£ 


carbon steel. 








0.04 basic 




Medium^. 


Open-hearth 


60k000 


28 


25 


0.05 acid; 


0.05 ! For test speci- 




carbon steeL 








0.04 basic 




mens below 
f^ in. in thick- 
ness, 180 deg. 
flat on itself. 
For test speci- 
mens ^i in. 
or more in 
thickness the 
bends will be 
180 deg. to a 
diam. of 1 


Hifffa 

tensile. 














thickness. 


Open-hearth 


aaooo 


25 


ao 


0.05 acid; 


0.05 


180 deg. to a 




carbon, nickel. 








0.04 basic 




diam. of l}4 




or silicon steel. 












thicknesses. 


Common. 


Opea-bearth 
or Bessemer 


55.000 


27 


22 


No chemical 
analysis re- 


180 deg. to 
a diam. of 1 




■ted. 








<l«ured. thickness. 



Steel Plates for HuUs (1916) 

Physical and Chemical Requirements. The phsrsical and chemical 
requirements and kind of material for plates shall be in accordance with 
TaUe 15. 

OalTanised Plates, (a) Physical and Chemical Requiremenis. Plates 
to be galvanised shall meet the requirements for steel of the grade specified 
before galvanising and shall conform to the permissible variations in weight 
and gage before galvanising. (6) Freedom from Surface Defects. Galvanised 
plates must be thoroughly and evenly galvanised; of a bright appearance; 
free from pits, blisters, and other defects; and must be commercially flat. 
No reroUing of the plates after leaving the galvanising bath will be permitted 
except for the purpose of straightening. The coating must not break o£F when 
scraped with a knife or if the plate is bent 90 deg. 

Bods for Bolts, Nuts and Studs (1916) * 

Steel rods for bolts and studs of the grade ordered shall conform to the 
requirements of Table 16. 



128 



IRON AND STEEL 



Grade 



Material 



Table 16 

-^ — 



|agts 



^ O Mi 



Maadmvm 
amount of 



P.. 
per cent 



S.. 
per 
cent 



Soft or flange 
steel. 



Medium steel. . 



High tensile, 
steel. 



Common steel . 



( SsToifss!: } »«" 



Open -hearth 
carbon steel 



Open -hearth 
carbon, 
nickel, or 
silicon steel 



60.000 



30 



O.QS 
0.04 



acid 
baaic 



0.05 



25 



0.05 
0.04 



add 
basic 



80.000 



Open - hearth; 55.000 
or Bessemer! 
steel. 



20 



22 



0.05 acid 
0.04 basic 



0.05 



0.05 



No chemical analy- 
sis required. 



Galdbend 



180 dec. flat on 
itself, 
r For material 
under 30.6 
lbs. per sq. 
ft.. 180 dec. 
flat on itself 
for longitudi- 
nal, and 180 
deg.toadiam. 
of 1 thickness 
for transverse. 
For material 
30.6 lbs. per 
sq.ft.andoTer, 
180 deg. to a 
diam. of 1 
thickness for 
longitudinal 
and 2 thick- 
nesses for 
transverse. 

180 deg. to a 
diam. of IH 
thicknesses 
for longitudi- 
nal, and 180 
deg.toadiam. 
of 2H thick- 
n e 8 8 e s for 
transverse. 

180 ,deg. to 
a diam. of 1 
tJiickness. 



Table 16. Physical and Chemical Requirements for Steel Rods 



Class 



Lbs. per sq. in. 



Material 



I Min. 
I tensile 
' strength 



Min. 
yield 
point 



Min. 
elonga- 
tion, 
per cent 



Max. 

amount 

of 



P.. I S.. 
per I per 
cent cent 



Bends 



A 


Open-hearth 
nickel or car- 
bon steel. 


75.000 


40.000 


23 


0.04 


0.045 


Cold bend 180 deg. 
about an inner 
diam. equal to H 
the thickness of the 
test specimen for 
diam. up to and in- 
cluding 1 in., and 
equal ue thickneas 






























for diam. over 1 in. 


B 


Open-hearth 


58.000 


30.000 


28 


0.04 


0.045 


Cold bend flat back 




carbon steel. 








1 ; through 180 deg. 


C 


Common steel. 








) 1 . 

1 1 



tested, unless this is considered fieCesKary by the Inspector to 



Grade C shall not be . ^ _, 

show that the material is equal to common steel of commercial quality 



STEEL, V. S, NAVY SPECIFICATIONS 129 

Matarial for nuts of steel or iron to be used with steel bolts or studs shall 
show a tensile streniEth of at least 48K)00 lbs. per sq. in. and an elongation of 
at least 26 per cent In 8 in. A specimen from full-eiied bar or one machined 
to ^ in. square or ^ in. in diam. shall bend back cold through an angle of- 
180 deg. without showing signs of fracture. 

Vpietting taste will only be required for material under 1 in. in diam. 
Specimens shall be cut about IH times the diam. of the round in length and 
shall be required to stand hammering down cold in a longitudinal direction 
to about H of the original leng^th of the specimen without showing seams or 
other defects in the manufactured product. The number of upsetting test 
specimens shall equal the number of tensile test specimens, but in no case 
shall it be less than 1 for each nominal diameter. 

Mftnufaetured Bolte, Nute and Studs (1915) 

Workmanship of Bolte. Bolts may be hot forged or upset cold; all 
bolts made by cold upsetting process must be. annealed after the heading 
operation; bolts must be free from sc^ale, abnormal fins, or other defects. 

Bending tests as specified in Table 16 shall be made on each bending test 
specimen, selected as specified above. In case the bolt is too short to permit 
this to be made on the unthreaded portion of the shank, the bolt shall be 
flattened out hot to a thickness equal to K of its diam., and this specimen 
when cold shall be subjected to the required test, using the new thickness of 
the specimen for purpose of this test, as the diam. on ^hich the bending tests 
are baaed. 

Tonsila Teste. The tensile specimens selected as specified above shall 
be subjected to a tensile test with the nut in plaoe, the stress to be applied on 
the bearing faces of the head and nut> unless die length of the bolt is too small 
to permit gripping by machine. The bolt must meet the tensile strength 
specified for the material called for by the order, and fracture must in all cases 
occur in the threaded portion of the bolt. When the order calls for bolts too 
short to apply the foregoing tensile test, tensile-test specimens may be selected 
from the rods from which short bolts are to be made in number as specified 
above. Bolts larger than l^i in. in diam. shall be tested by turning there- 
from IM-in* studs. These studs shall be tested in a like manner as specified 
for testing bolts, by fitting a 1^-in. nut at each end. In determining the 
tensile strength of the bolt the mean thread area will be used as representing 
the effective area. 

Workmanship of Huts. Nuts shall be either hot forged or cold punched 
from a solid bar. They must be free from scale, fins, seams, or other inju- 
rious or unsightly defects, and must have clean and smoothly threaded holes 
of nominal siae, square to the end faces of the nuts. 

Physical Test of Nute, Bteel or Iron. One-third of the specimens 
selected shall be drifted cold until they break. The fracture must indicate 
homogenous structure of the material. If the material is wrought iron, the 
fibers must run at right angles to the axis of the hole. 

One-third of the specimens selected shall stand flattening out azially, 
cold, to H the original thickness without showing cracks in the case of steel 
or craeks of any considerable sise or number in the case of iron nuts. 

The other third shell stand flattening out azially, when heated to a 
eliaiTX red in daylight, to H the original thickness without showing cracks 
in the case of steel or cracks of any considerable sise or number in the case of 
iron nuts. 
9 



130 



IRON AND STEEL 







I 

'^.§•6  ""O ^ ^ 

8gi"-5Ss.s ^ ' - - » 



5i • 



•d .•« 






A0«« • 
•«'a 3 

al |.s 









I ft4 



M I.-** 



nm 



8 

6 






3 I — 



O 

•a 

8 



5^ 



•8 



I 



i 



^ » 



SiQ ^ 






I 



;2s a 



if 




i 



I- 



a 
5 







• • • 




5 i5 


ij is 


^^ « 


• • 


to • 


m m 




B m 


1 1 


S 1 


§1 § 


1! 


M^ »n 


»n lA 




lA »rt 


e e 


e e 


.oo o 


o e 


1 

000 
000 


§ § 




3* s- 

5 5 




II 1 


1 1 


§ § 


§ § 


i^ i 


% t 


«• S? 


^ ^ 


— 






w^ i/N 




S : 


s s 


%% s 


8 8 


e 


e o 


' ed d 


e e 



8 8 



S S 



S8 S 



S 8 



S S 



o o 



SS 8 



S S 



I- 

A A 



M 

a « 



B 



1^ S 2St*3 
«2 I ^r-^' 



^ ^ 






.2 b 
SO 6 

IE 8 •.! 



I 



.9 



arSKL. V. S. tIAVY aPtClFlCATiOHS 



131 



ilSi3|e| 



ill 



J 5 1 2 



Iiil 


llll 


B H) Bj Bi 

■d no «dBid 
as SS 28S8 


d d a  
nd md ndoid 
5S SS SS58 

0» C>C3cfdd^ 



i-31 



Jiliiii 



T«aU of Btudl. Studs thaU be tMMd in the 

a&me manaec as prescribed for bolts. 

Uhi. CloMt A ateel bolts are uied for atuJt 
ooupliogs. bolts for thruet-beorios side rods, maui 
engiiie (ramiog, cylinden or vslve cheat covera. 
valve bonoeta, main beuing-oap bolta, and for 
eecurins parte of machinery. Clan B eteel bolta 
or etude are used in pipe flangee, ralvee beoeath 
floor platee. ooaaeoting rod plugs, and for struc- 
tural purpoeee. Clot* C steel bolts are used with 
plates, ebapea. etc., where atrength is not im- 

piHtSDt. 

Nonferrous bolta and nuta are uaed where ex- 
posed to Bction of salt water or where nonmasnetio 
material it required. 

StmotuTAl Iteel Work 



^i.|- 



!* I M 



>%i.iu-i4i^ , 



Pb>. 12. 



for remforoement bare may be made by either the 
Beeeetoer or the open-hearth piocesa. 

CtwmicAl and phrilcfti propartlei shall cou- 
lorm to Table 17. 

Spedinwu tor tenilla *nd btndlnf teata 
lor pUtei, ^»pai, and bari aball be cut from 
the floiahed produrt, and shall have both iBces 
rolled and both edges milled to the form ahown 
by Fig. 12, or have both edges parallel through- 
out; or, they may be turned to a diam. of *i in. 
for a length of at loaat in., with enlarged ends. 
"a Teet ipecimena or rlTSt iteal shall be of the full 

J' s aise of the rod- 
^■3 Specimens repreeenting Itael csatlnBt shall be 
^1 made from coupona which are molded, rast. and 
|.a anoealed aa integral parte of the castinga and which 
1 1 are not cut from the castinga until after the corn- 
las' pletioa of the annealing proceea. Test specimens 
I I for tensile teste shall be of the form shown in 

^ Individual coupon tests and reports will be made 
^ for each haat unless otherwise elsewhere specified. 



}32 



IRON AND STEEL 



noor Plates (1918) 

Floor plates for use in engine and boiler rooms, in machinery spaces and 
similar locations shall be made of Bessemer or open-hearth Ateel. 




;f 



K % H < 



♦t^/^ 



f\o. 18. 



Nickel-Steel Plates (1917) 

Method of Manufacture. Nickel-steel plates shall be manufaetured by 
the open-hearth process; all plates shall be oil or water tempered and annealed, 
and the whole of each plate shall be subjected to the same treatment at the 
same time. 

Chemical Bequirements. Plates shall contain not lesis than 3 per cent 
of nickel, not more than 0.05 per cent of phosphorus, nor more than 0.($45 
per cent of sulphur, and shall be of the best composition in ill other respeots. 

Physical Bequirements. All tests shall be made uponi specimens taken 
from plates after final treatment. 

Tensile Tests. One longitudinal specimen for tensile tpst will be taken 
from each plate. Each test specimen shall show a tensile strength of at 
least 80,000 lbs. per sq. in. and an elongation in 2 in. of at least 27 per cent. 
All tensile test specimens shall be taken from a location at the end of the plate 
nearest the bottom of the ingot from which the plate was rolTed. 

Gold Bendinir Tests. Two longitudinal pieces cut from different plates 
in each heat, shall be doubled cold around a mandrel, the diam. of which is 
not more than the thickness of the piece tested, without showing any cracks. 
The ends of the pieces shall be parallel alter bending. 

Flat Black and Oalyanised, and Corrugated Oal?aniaed Sheet Steel 

(1916) 

Quality shall be as follows: 

Black sheets shall be made of a high-grade steel of a quality that will 
stand double seaming without cracking; shall be commercially flat and iree 
from scale, pits, laminations, buckles or any other injurioud defects. 

Oalvaniz&d sheets shall be thoroughly and evisnly g^vanised with sine, 
in a bath which shall show not less than 98 per cent pure zinc; eoating pro- 
duced shall be of a bright appearance and shall not flake or peel off when 
scraped with a knife, or when the sheet is bent sharply at right angles. Sheets 
shall be free from blisters, ragged edges, buckles, laminations, and other 
injurious defects. 

Steel flat galvanized sheets shall be made of the same quality of steel as flat 
black sheets; shall stand double seaming without cracking; and shall be 
commercially flat. 

Steel corrugated galvanized sheets shall be of a good grade of steel, but shall 
not be subjected to the double-seaming test. 



STEEL, U. S. NAVY SPECIFICATIONS 



133 



Cold-roil«d or Cold-drawn Machinery Stoal Bodi and Bars (1917) 
Physical and chemical requlremente of cold-rolled or cold-drawn steel 
shall be in accordance with tables 18 and 19. 

Steel, Welding, Wire and Bod (1917) 
Uses. This material is suitable for electrical and autogenous welding of 
steel eastings, fcrgingB, etc. 
Chemical composition shall conform to Table 20. 

Table 18 



Ultimate 
tensile Btrencth 
lbs. per sq. in. 



Min, 
yield 
point, 
per 
oent 



Type 

of teat 
pieces 



Minimum 

elongation, 

per cent 



ChsB A: 

Bted rods and 

Under }^m. ia diam. or thiakneea 

yi in. to hi in. inclusive, in diam. or 
thickness 

Orer }i in. tx> IH in. inclusive, in diam. 
or tmcknesB 

Over IH in. in diam. or thickness.. 

Claae B: 

Steel for automatic screw or bolt 
machines 



(0 

SOlOOO-IIOLOOO 
1 75.000-100.000 
701000-90.000 

!' 7aooo 



(*) 

75 ult. 
75ult. 
70 ult. 

50 




(«) 



12 in 2 in. 

10 in 8 in. 
16 in 2 in. 
14 in 8 in. 
18 in 2 in. 

6 in 8 in 
10 in 2 in. 



I No physical tests required. 

Table 19 



* As for class A. 



Maximum amount 
of 



Phosphorus 
per cent 



Sulphur, 
per cent 



Cold bend 



CUSS A: 

Steel rods and bars. . 
Class B: 

Steel for automatic 
machines 



screw or bolt 



0.06 
0.13 



0.06 180 deg. to 8 diam. 



0.15 I 120 dPK. to 3 diam. 



Table SO 



Grade 



Carbon, 
per 
cent 



Silicon. 

(max.) 
per 
cent 



Mansanese 
per 

cent 



I 



I to 0.25 
0.40 to 0.60 




lifild steel or, 

iron 0to0.T2 0.10 

Nickel steel. 0. 20 to 0.30 0^20 

^cm.—Mfld stee! or iron must not contain more than a trace of copper, nickel, or 
efaromittn). 

Spring Steel, Rolled and Drawn (1917) 
Process of Manufacture. Spring steel may be manufactured by either 
the open-hearth, crucible or electric-furnace process. 

Classes. Rolled spring steel shall be furnished in either of the two fol- 
lowing classes, as specified: Class A, cjarbon. 0.70 to 0.90 per oent; class 



134 IRON AND STEEL 

B, carbon. 0.90 to UIO per cent. Drawn Aping steel shall be fumished in 
cither of the two following classes, as specified; ClMft C, a carbon drawn 
acid steel; class D, an annealed, carbon steel, not tempered. 

Chemical Beqiiireinents. The required percentage chemical contents 
of the above four classes shall be as follows: BoUed spring steel class A; 
carbon, 0.70 to 0.90; manganese, 0.25 to 0.50; silicon (max.), 0.25; sulphur 
(max.), 0.05; phosphorus (max.), 0.04. Rolled sprixi^ steel gIms B; 
carbon, 0.90 to 1.10; manganese, 0»25 to 0.50; silicon (max.), 0.25; sulphur 
(max.), 0.05; phosphorus (max.), 0.04. In both classes of rolled spring steel 
vanadium or other elements may be used, in which case only the phosphorus 
and sulphur requirements as given above need be adhered to. The bidder 
shall state, however, in his bid whether he proposes to furnish material meet- 
ing the composition specified or alloy steel; if the latter, what approximate 
composition, naming all elements. 

The percentage chemical contents of drawn spring steel class C will 
be: Carbon 0.55 to 0.65; manganese, 1 to 1.25; silicon, 0.12 to 0.20; sulphur 
(max.), 0.05; phosphorus (max.), 0.04. For drawn spring steel class D: 
Carbon, 0.78 to 0.85; manganese, 0.40 to 0.55; silicon, 0.12 to 0.20; sulphur 
(max.), 0.05; phosphorus (max.), 0.04. 

Tests. From each lot of 20 bars or fraction thereof, of the same size, 
made from the same open-hearth melt or furnace charge, one bar shall be 
selected at random and subjected to a nick-and-break test. The nick-and* 
break test will be made on the full-size specimen. 

A specimen, when nicked and broken, shall present a fine uniform grain 

Steel Slabs, Blooms, Billets, and Bars for Beforging (1918) 

Process. Ingots from which billets are made shall be manufactured by 
the open-hearth, crucible, or electric-furnace process. Billets shall be 
rolled or forged from ingots having a cross-sectional area of at least 4 times 
the cross-sectional area of the finished billet up to 18 in. ; over 18 in. the cross- 
sectional area of the ingot shall be not less, in any case, than that required 
for an 18-in. billet and that area should be increased as necessary in order 
that the ingot shall in each case have a cross-sectional krea not less than 3 
times that of the finished billet. 

Discard. Sufficient discard shall be taken from each ingot to insure free- 
dom from piping and undue segregation. Such discard shall be not less than 
6 per cent of the total weight of the ingot taken from the bottom and 30 
per cent from the top if top poured, and 5 per cent from the bottom and 20 
per cent from the top if bottom poured or fluid compressed. When forgings 
are to be made from bored fluid-compressed ingots at least 3 per cent of the 
total weight of the ingot shall be discarded from the bottom and at least 10 
per cent of the total weight from the top. 

Surface and Other Defects. All billets shall be free from seams, pipes, 
flaws, cracks, blowholes, hard 8pot«, sand, foreign substances, excessive slag, 
and all other defects affecting their value. 

Chemical Bequirements. Billets will be accepted on chemical analysis 
only and shall be within the requirements of the grade as specified in Table 21. 

Treatment. No definite mechanical xvoperties are required for mate- 
rial covered by these specifications. The manufacturer shall, if requested, 
furnish the inspector with a description of the heat treatment which is 
guaranteed to produce mechanical qualities as given in Table 22 for the n^ 
Bpeotive grades. 



STBBL, U. S. NAVY SPBCIPJ CATIONS 



135 



Table 21 



Grade 



Carb<Mi, 

per 

cent 



Manga- 
nese! 
per cent 



Sulphur, 

per cent 

max. 



Phon- 

phOTUV, 

per cent 
max. 



Nickel, 

per cent 

min. 



Alloy Nn. I 


0.50 max 


AlU^ No. 2 


0.50 max 


AlW No -^ . 


0.45 max 


HG..... 


0.30-^.45 


Ail •. . 


0.25-4).45 
0.40-0.60 
0.4(M).60 
0.25-0.40 


Ac 


B— 8 (special) 


B 


C 




S 


0.06-0.15 



0.40-0.80 
0.40-0.80 
0.40-0.80 
0.40-0.80 
0.4S-0.70 

6!3ChO.'56 



0.035 

0.035 

0.04 

0.045 

0.045 

0.045 

0.045 

0.045 

0.07 

0.04 



0.03 
0.03 
0.04 
0.04 
0.04 
0.04 
0.04 
0.04 
0.07 
0.04 



3,0 
3.0 



Table 22 

Minimum vliluet 




a— 

id 



Gradr 






•** 
^ a 

111 
II sr 

&^ 



i 



Cold bend 



Alloy Nq. 1. . . 
Alloy No. 2. . . 
Alloy No. 3... 

HG 

An 

Ac 

B^~B (special) 

B 

C 

S 



1701000 


I40l000 


10 


l%000 


105.000 


20 


fO5.000 


80.000 


20 , 


95.000 


65.000 


21 


oaooo 


50.000 


25 1 


80.000 


45.000 


25 


75^000 


40.000 


22 


6aooo 


30.000 


30 


50.000 




18 


46.000 


HOOO 


32 



8 
15 
18 
18 
21 
21 
19 
25 
15 
28 



None required. 
None required. 
180 deg. to inner diam. of 1 in. 
180 deg. to inner diam. of 1 in. 
180 deg. to inner diam. of 1 in. 
180 deg. to inner diam . of 1 in. 
180 deg. to inner diam. of 1 in. 
180 deg. to inner diam. of ^ in. 
None required. 
180 deg. flat. 



Hot Boiled or Vorged Alloy Steel (Chrome Vanadium) 
Method of Manufacture. Special alloy steel bought under this speci- 
fication must be manufactured either by the electric, crucible, or open-hearth 
proceeB, depending on which process is specified in the requisition. 

Slabs, Blooms, and Billets. All slabs, bloomy,, billets, oi other forgings 
of special alloy steel shall be rolled or forged from ingots whose cross-section 
is at least twice that of the finished slab, bloont, or billet, and from ingots 
from which a discard of at least 5 per cent of the total weight has been taken 
from the bottom and 30 per cent from the top, if top poured ; 5 per cent from 
the bottom and 20 per cent from the top if the ingot has been bottom poured 
or fluid compressed. 

Chemical Composition. Special alloy steel to be bought under this 
epecificatioD must coniorm to the chemical composition given in Table 23. 

' Table S8 



Per cent 



T 



Carbon.. . . 
Sulphur. . . . 
Manganese. 
Vanadium. , 
Chromium. 
Phoephorus 



0.35-0.45 
Not to exceed 0.04 
0.50-0.80 
0.12-0.25 
0.70-1.10 
Not to exceed 0.04 



Per cent 
desired 

0.40 

' 'i'.ii'" 

0.18 
0.90 



136 



IRON AND STEEL 



Steal Forginfs for Hulli, Bngines, and Ordnance (1918) 

Ugei. Table 24 gives the uses to which the various grades of st^el 
forcings are adapted. 

Table 24 



Material 



Class 



Engine forgincs. . 



Engine f orginits. . 



Engine forgings. 



Engine f orgings. . 



HG 



An 



B 



Purpose for which used 



Bolts and studs for all moving parts of main engines; shaft 
couplings, main-bearing caps, thrust-bearing side rods, 
main-engine frsjuing, and moving parts of circulating 
pumps; connecting rods, caps, ana bolts; eccentric rods; 
main circulating-pump engine working parts; piston rods; 
suspension links and hnk blocks: valve stems. 
Coupling bolts; crossheads and slippers; crank, thrust, line, 
stern tube, tail, and propeller shafts; main-bearing cap. 
bolts; outboard coupling;; revense arms and blocks; rotor 
shaftj thrust-bearing side rods; turning engine worm; 
working parts, reversing gear; workinp; parts, pumps. 
Bearer bars; turbine rotor shafts; engine columns and tie- 
rods; H. P. relief-valve stems; main steam vahre stems; 
main-bearing cap bolts; piston-rod nuts; piston- valve 
followers; pioe flanges; rotor drum and wheel; sole-plate 
wedges; swivel pins for crosshead; working levers and gears. 
Gland for cylinder liners; small parts for eccentrics; uptake 
and smoke-pipe forgings. 



All steel forgings will be without welds and free from laminations. 

All Class HG steel forgings 5 in. or more in diam. wiU have axial holes of 
approved diam. 

The working parts of all auxiliary machinery, unless otherwise specified, 
will be made of class A nickel-steel forgings. 

All steel pistons rods and valve stems of auxiliary engines will be oil 
tempered. 

All steel joint pins of valve gear will be hardened and ground to true 
cylindrical surfaces. 

All small pins of working parts will be well ease-hardened and ground. 

Drop forgings of parts subject to pressure or strains must meet the phys- 
ical and chemical requirements of Class B forgings. Drop forgings of parts 
not subject to pressure will be required to have surface inspection only. 

Process. Steel for forgings shall be made by the open-hearth, crucible, or 
electric process. They shall be forged or rolled from ingots, the original 
cross-sectional area of which is at least 4 times that of the finished forgings. 
Class C forgings may be made by the Bessemer process. 

If bored ingots are used the Wall of the ingot shall be reduced to at least 
}4 of its original thickness, or the reduction of area shall be at least 4 to 1. 
Palms, flanges, and other enlargements on shafting, need not be reduced in 
the ratio of 4 to 1, but shall be reduced in a ratio of not less than 1.7 to 1. 

Discard. Suflicient discard shall be taken from each ingot to insure 
freedom from piping and undue segregation. Such discard shall be not less 
than 5 per cent of the total weight of the ingot taken from the bottom and 
30 per cent from the top if top poured, and 5 per cent from the bottom and 
20 per cent from the top if bottom poured or fluid compressed. When 
forgings are to be made from bored fluid compressed ingots at least 3 per cent 
of the total weight of the ingot shall be discardcni from the bottom and at 
[east 10 per cent of the total weight from the top. 

Surface &nd Other Defects. All forgings shall be free from seams, pipes, 
flaws, cracks, scale, fins, porosity, hard spots, sand, foreign substances, 
excessive slag, and all other defects aflfecting their value. 



■II 



-|r! 









rm 



^m 



.ass la in^i§. 

'sle |e lals^E 
■4s4 S=3 s=ssli« 



£!3 S ^ » 



III I I g I § 



§§§§ § §§§| 

as s s s s K g s 



S&S2 3 3S3S 



gssi § Ssis 



SS 3 9 « 3 S 9 



|& -Si 



•|fe -jt I 2 I I 

|\|! J i i i 

-| a Eg a 6u O O (3 



I 

< a ffl d 






I Si's 



138 IRON AND STEEL 

Chemical and Phytioal Properties. The respective classee of forgingB 
shall have the properties given in Table 25. 

. Test SpecimeiiB shall fairly represent the average strength of the 
material and shall be taken at a point which has received the average amount 
of reduction. They should, in general, be located in that part of the forging 
which includes the uppermost part of the ingot as cast. 

Types of Porgixi^. Coyered by Oeneral Requirements. Parts of 
gun recoil system, including recoil and spring cylinders, piston rods; also 
nuts and bolts for same. Gun elevating and training gear shafts, worms, 
pinions, keys, and feathers, etc., for same. Parts of gun mounts, such as 
gun yokes, trunnion- bearing cape, floating supports, and other trunnion parts, 
trunnion bands, and slides. Parts of torpedo tubes and ordnance appurte- 
nances, shafting, rammer, links, etc. Turret roUers, turret^tuming pin- 
ions, turret racks, and tracks. Armor keys. Holding-down bolls for gun 
mounts and turret tracks. Rudder frames and rudder stocks. Anchor 
crane stocks. 

Metallographic examination for purposes of record and information 
may be made on any forging, but such examination shall not cause rejection 
if otherwise satisfactory except in the case of propelling machinery shafting 
and couplings for vessels. All propelling machinery shafting and couplings 
for vessels shall be subjected to photomicrographic examination, and accept- 
ance shall depend on the result of such examination. 

Metallographic Requirements. Specimens when examined at a magni- 
fication of 100 shall show a homogeneous structure— -t.e., one in which the 
normal constituents are evenly distributed, free from decided segregation of 
any constituents, ingotism, or excessive impurities. Grains with any dimen- 
sion greater than H in. in diam. at 100 diam. (Hoo in.) will render the forging 
liable to rejection. In these specifications the term grain shall be taken to 
include the constituents which together made up the austenite cell from which 
the constituents were last evolved. If the outlines of this cell are not clear, 
the uninterrupted areas of the predominant metfJlographic constituent 
shall be used in determining the grain sise. 

Steel Gastinffs (1918) 

Uses. Grcuie A is intended for all important parts subject to crushing 
stresses or surface wear only, such as hawse pipes, chain pipes, turret roller 
paths, engine guides, slippers, etc. 

Grade B is intended for parts subject to tensile or vibratory stressoo. such 
as stems, sternposts, stern tubes, rudder frames, struts, engine bedplates, 
cylinders, gun-mount stands, carriages, slides, and other parts subject to the 
shock of recoil. 

Grade C is intended for gun mounts, such as brackets, levers, wheels, etc., 
not subject to shock of recoil, and for commercial fittings where structural 
strength and separation of watertight compartments are not involved, such 
as pipe flanges (other than bulkhead and deck), cagemast fittinss, stowa^^ 
lugs and clips, hinges for doors and hatches where wat'Crtightness is not 
involved, etc. 

Grade D is intended for the same general purpose as Grade B, but where 
greater strength is required with equal ductility. 

Grade E is intended where design will permit its use for castings for similar 
purposes as Grade F. 

Grade F is intended for castings for gun yokes, gun-mount stands, carriasee, 
slides, deck lugs, e»c., of large sise. 

Cast-steel H.P. pipe fittings will be Class B. Caet^teel L.P. pipe fittinas 
may be Class C 



STEEL, U. S. NAVY SPECIFICATIONS 



139 



Castings forming a bearing surface will be of special mixture to secure a 
dose-grained hard surface. 

All flanges, collars, and oflFsets will have well-rounded fillets, and ample 
fillets wUl be provided in oth«> places where necessary. 

The metal of important castings subject to pressure must be homogeneous 
and the thickness of no part will be allo'W'ed to deviate materially from the 
dimensions shown on the approved drawings. Special steps will be taken 
to guard against porosity. 

The Chemical and Physical Properties of steel castings shall be in 
accordance with Table 26. 

Table S€ 





C h e m ical oompoeition. 
maximum 


Physica] requirements 


Grade 


Tropenas 


Open- 
hearth, 
electric 
furnace, 
or c r u cible 


Mini- 
mum 

tenaile 
strength, 


Minimum 

yield point, 

Ib9. persq.in. 


Mini- 
mum 
elonga- 
tion, 
per cent, 
in 2 in. 


Mini- 
mum 
reduc- 
tion of 

area, 
per cent 


Cold 

bend 

about a 

diam. of 




P. 1 8. 
per , per 
eent cent 


P. 

per 

cent 


8. 
per 
cent 


Ibe. per 
sq. in. 


1 in., 
deg. 

1 


F 

E 

A 

D 

B 

C 


0.05 0.05 
0.05 0.05 

0.05 , 0.05 
0.05 0.05 

0.06 ' 0.06 

1 

0.06 0.06 


0.05 
0.05 

0.05 
0.05 
0.06 

0.06 


0.05 
0.05 ' 

0.05 
0.05 
0.06 

0.07 


85.000 
80.000 

80.000 
70.000 

6aooo 


53.000 

44.000 
45 per 
cent of, 
tensile, 
strength 
obtained. 


22 
22 

17 
22 
22 


35 
30 

20 
30 
30 


120 
120 

90 
120 
120 



Welding. Surface defects and cavities which are of more than minor 
importance shall not be so welded except by permission of the Inspector 
in charge of the district. In no case will any welding be allowed on steam 
piping or any other casting used in connection with steam piping or subjected 
to steam pressure, nor in the following ordnance castings: Gun yokes and 
slides in region of the trunnions, elevating gear lugs, and recoil cylinder and 
spring cylinder bearinss for same. 

Treatment. Rapid cooling of the castings by the rise of water, brine, oil, or 
air blast will be permitted only with the specific approval of the Inspector. 

All castings shall be carefully annealed so that any fracture shall show to 
the eye a fine-grained structure. The grain sise may be determined by the 
appearance of the fracture of the test coupons representing the casting in 
question. 

Test Bpedmens. Coupons from which test specimens are to be taken 
shall, whenever practicable, be cast on the body of the casting. 

Percussive Test. Large castings when required by the inspector shall 
be subjected to hammer tests, aa follows: The castings shall be suspended and 
hammered all over with a hammer weighing not less than 7H ^^* ^U under 
such treatment, cracks, flaws, defects, or unsoundnesses are indicated which 
render the castings unfit for service, such castings shall be rejected. 

Metallographic Bzamination. For the purposes of information and 
record only, and having no bearing upon the acceptance or rejection of the 
material represented thereby, from two castings weighing 200 lbs. or over 



140 



IROK AND STBRL 



in each heat containing two or more such castineB, teet pieces shall be taken 
for metallographic examination ; in case a heat should contain only one casting* 
weighing 200 lbs. or over, one test piece shall be taken from that casting. 
These test pieces shall be sections of the broken tensile test bars. 

Carbon Tool Steel 

Uies. CUua 1, drill rods, lathe and planer tools, and tools requiring keen 
cutting edges combined with great hardness, such as drills, taps, and reamers. 

Clcus 2, milling cutters, mandrels, trimmer dies, threading dies, and general 
machine-shop tools requiring a keen cutting edge combined with hardness. 

Class 3, pneumatic chisels, punches, shear blades, etc., and in general tools 
requiring hard surface with considerable tenacity. 

Class 4, rivet sets, hammers, cupping tools, smith tools, hot drop-forge dies, 
etc., and in general tools which require great toughness combined with the 
necessary hardness. 

Class 5. gauges and articles of all types which require a medium degree of 
hardness for the purpose of resisting wear and abrasion, combined with a 
minimum of deformation during the process of hardening. 

Method of Manufacture. The tool steels must be made in either the 
electric or crucible furnace and must be of homogeneous composition. The 
bars or rods shall be forged or rolled accurately to the dimensions specified, 
and must be free from seams, checks, and other physical defects. They must 
be delivered annealed and, unless otherwise specified, in commercial lengths. 
Short pieces will not be accepted. Drill rods roust be coated with a rust 
preventive. 

Chemical Bequlremente of carbon tool steel must be in accordance with 
Table 27. 

Table S7 



Class 1, per 

cent of 

limit 



Max- 
imum 



Min- 
imum 



Class 2, per Class 3, perl Class 4, per'iClass 6, per 



cent of 
limit 



Max- 
imum 



Min- 
imum 



cent of 
limit 



cent of 
limit 



cent oi 
limit 



Max- 
imum 



Min- 
imum 



Max- 
imum 



Min- 
imum 



Max- 
imum 



Min- 
imum 



Carbon ! L35 

Manganese 0.35 

Phosphorus I 0.015 

Silicon I 0.40 

Sulphur 0.02 

Vanadium 0.00 

Other elements' 



1.20 


1.10 


1.00 


0.90 


0.80 


0.80 


0.70 


1.05 


0.15 


0.35 


0.15 


0.35 


0.15 


0.35 


0.15 


2.00 


0.00 


0.015 


0.00 


0.02 


0.00 


0.02 


0.02 


0.00 


0.10 


0.40 


0.10 


0.40 


0.10 


0.40 


0.10 


0.50 


0.00 


0.02 


0.00 


0.025 


0.00 


0.025 


0.00 


0.025 


0.00 


0.00 


0.00 


0.00 


0.00 


0.00 


0.00 


(») 



0.80 
1.25 
0.00 
0.25 
0.00 
0) 



> Optional. ' As submitted. 

Inspection. Access to the records of the manufacturers to identify heat 
numbers and other information of assistance to the Inspector shall be allowed. 
The Inspector will assign a lot number to all the material submitted for inspec- 
tion at any one time and will forward to the Engineer Officer, with forms 
provided for the pmpose, samples for chemical analysis on the basis of one 
sample for each 500 lbs. or fraction thereof of material submitted. The 
sample to be about 1 }i ounces of finely divided drillings. 

Samples for SelectiYe Test. Each bidder shall furnish with his proposal 
sample bars of tool steel, stamped as specified, for the "selective test.*' 
The relation of the results obtained from the tests conducted as provided for 
under the heading ** Selective tests" and the price of the material determine 
the selective fact4>r. At the discretion of the bureau concerned, bidders who 



STBBL, U. S, NAVY SPBClFTrATWyS 



141 



have i>ievioiialy submitted eamplee identioal with m»torial ofleted may be 
daaaified sccording to the sedective factor previously determined. 

The dimenaioDS of the sample bars shall be as follows: 

Clou 1 . ^ H 6 inch diameter rod, 2 )^feet long. 

Ckua 2. ^ K 6 inoh diameter rod, 2 H foot long. 

Class 3. fi inch octagon rod^ 5 feet long. 

Class 4. 2 inch diameter rod, 2 feet long. 

Class 5. 1 piece 5ii inches in diameter, 9 inches long; 1 piece 2 inches in 
diameter, 12 inches long. 

Ttvatntsnt of Samptot. Each bidder will state in his proposal, if he con- 
siders it necessary to do so, the treatment to which the material must be 
subjected in order to get, in his opinion, the best results. 

8«lsetiTS Tests. Class 1. Five Ke in. diam. 4-tooth facing mills will be 
made from the sample rod and tested on a piece of ^-in. ship's plate without 
lubricant. Each mill will be run until it is so dull that it breaks either in the 
teeth or in the shank. The depth of cut will be 0.08 in., the revolutions per 
minute of the mill will be 370, and the feed of material 20 in. permin. A 
record will be made of the length of time each mill operates. 

Class 2. Five J^e in. diam. 4-tooth facing mills will be made from the 
sample rod and tested on a piece of ^^-in. ship's plate without lubricant. 
Bach mill will be run until it is so dull that it breaks either in the teeth or in the 
shank. The depth of cut will be 0.08 in., the revolutions per minute of the mill 
will be 370, and the feed of material 20 in. per min. A record will be made of 
the length of time each mill operates. 

Class 3. Five H'in. pneumatic chisels will bejnade from the sample bar. 
Each chisel will be tested on a nickel-steel plate with a cut of }{e in. deep. 
A record will be made of the distance each chisel cuts with a lubricant before 
it is ruined 

Class 4. Two }j-in. rivet sets will be made from the sample bar. A 
record will be made of the condition of the sets after a certain number of 
rivets have been driven. 

Tiinfiten Tool Steel 

Ums. Class 1, drill rods, lathe and planer tools milling-machine tools, 
and in general all tools for which high-speed steel is used. 

CZass 2, lathe and planer tools ai^d general machine-shop tools which require 
a keen and durable cutting edge. This material is adapted for brass finishing 
and other finishing work. 

Method of Manuf ACture, see Carbon Tool Steel. 

Chemical Requirements of tungsten tool steel must be in accordance 
with Table 28. 

Table tB 



Class 1. per cent of 
limit 



Carbon 

Chromium 

Manganese 

Phosphorus 

Silicon 

Sulphur 

Tungsten 

Vanadium 

Other elements, as submitted 



Maximum 

0.75 
5.00 
0.45 
0.02 
0.40 
0.03 
20.00 
2.00 



Minimum 



Class 2, per cent of 
'limit 

Maximum Minimum 



0.45 
2.50 
0.15 
0.00 
0.10 
0.00 
12.00 
0.70 



1.50 
0.00 
0.35 
0.02 
0.60 
0.03 
5.00 



1.35 
0.00 
0.15 
0.00 
0.10 
0.00 
3.00 



142 



IRON AND 8TBEL 



Table M. Condensed Chemioal and Fhjnieal Requirements of 



T 



Material 



S 

s 



a 
i 



I 

. a 

I 



9 

»• 

O 

M 

I 

.a 

A4 



3 

OQ 



S 



QC 



8te«l boiler tubea ' 0.06-0.18 0.30-0.50 

Welded steel pipe 



Flange steel 

Fire box steel . . . 
Boiler rivet steel. 



I 
0.12-0.25 



0.04 



Structural steel for buildings. . 

Rivet steel for buildings 

Structural steel for bridges 

Rivet steel for bridges 

Structural steel for ships •. 

Rivet steel for ships 

Structural nickel steel 

Structural rivet nickel steel. . . . 



0.30-0.60 O.OSa 
0.30-0.50 ;0.§4a 
0;3O^.5O 0.04 



0.046 
0.35b 



Steel rails, Bessemer. . . 
Steel rails, open-hearth. 
Steel tires 



Steel bars for springs 

Silico-manganese steel bars for 

springs 

Chrome-vanadium steel bars for 
springs 



Blooms, billets and slabs for 
carbon steel forgings. 



Carbon steel forgings for loco- 
motives, unannealed. 



0.45 
0.30 max. 



0.06 



0.045 

0.05 
0.04 
0.045 



0.045 



0.06a 0.04b I 0.05 



0.37-«.55 
0.50^.75 
0.50-0.85 



A 
B 
C 
D 
E 



0.85-1.15 
0.45-0.65 
0.45-0.65 



0.04a 0.04b 

0.06a 0.04b 

I 

0.06a 0.04b 
0.70 max. 0.05a 0.04b 
0.60 max. |o.04a 0.03b 



I 



0.80-1.10 
0.60-0.90 
0.75 



0.10 
0.04 
0.05 



t •  • • 

• • • • I 



0.05a 



0.08-0. 1() 
0.15-0.25 
0.25-0.38 
0.38-0.52 
0.45-0.60 



0.25-0.50 
0.50-0.80 0.05a 
0.5O-O.90 !o.05a 



0.30-0.50 0.045 

0.3a0.50 0.045 

0.40-0.60 0.045 

0.40-0.60 0.045 



Carbon steel forgings for loco- 
motives, annealed. 




0.45-0.70 



0.40-0.70 



0.045 



0.04b 

0.045b 

0.04b 



0.05 



0.045 

0.05 

0.045 



0.20 
0.20 
0.05 0.15-0.35 



• • • « • 



*  •  ' 



0.05 

0.045 

0.05 



1,50-2.10 



0.05 
0.05 
0.05 
0.05 
0.05 



0.40-0.70 0.05 



0.40-0.70 0.05 ' 0.05 



0.05 
0.05 



0.40-O.70 
0.40-0. 70 



0.05 
0.05 



0.05 
0.05 



STBSL. A. a. T. M. SPKCIFICATWNB 

It ■•ctrty for tnUat ItotwlaU fi »f 1. 





- 

B 
1 


s 

1 


DUm- 

•t«r 


Hi 


A 




ft 

ill 


a.a£ 


u«,i>er»iit 


1 




m 
ill 


11 


1 








• 
















» 

«-« 

«-5i 


30 
D.5T 
0.5 T 
0.5 T 


B. 

a 
a 


t.8. 




1 


1 




/ 


5i-6S 

55-65 
46-56 

55-65 
S5-lin 
7(M0 


(I.5T 

0.5 T 
0.5 7 
O.ST 
0.5 T 
0.5 T 
50- 
45 


8. 

8. 
B 

s 

■5 


MOOJMp 

imooo 

i.io6.ooo 

1 


21 

16-20 

.... 


'is-ss 

« 












MJ^is 






Vii 












11-16 
























Lm-i.i» 


B.IS 






















































:::::::;:: 








'EE 








:::::::: j:::::: 









 


• 


75 
75 


0.5 T.B. 




IS 
IT 


zioaooo ,^ 

5.S.!" 









12 


11 

2D 


10 
M 
M 


0.5T 
0.5 T 
9.5 T 


a. 

B. 




20 
19 
l« 


umno 

#■ 
i4(aoot 

"T.sT 


32 

30 

a 



144 



IRON AND STEEL 



Table S9. CohdenMd Ofaefliioftl and ThfwitalB^q^ixwnmmU «f 



Material 


J 




1 


Manganese 


9 

1 

a 

s 

0U 


hi 

9 
00 


1 




• • 

• • 

A 

B 
B 

C 
C 

D 
D 
D 


0.25-O.60 
0.35-0.60 
0.35-0.65 
0.35-0.70 


0.4O-O.70 
0.40-0.70 
0.40-O.70 
0.40-0.70 


0.05 
0.05 
0.05 
0.05 




0.05 




Quenched and tempered carbon 


0.05 




Bteel axles, shafts, etc., for loco- 
motives and cars. 


0.05 
0.05 
















0.30-0.55 
0.4O4).80 
0.40-0.80 


0.05a 
0.05a 
0.05a 


0.056 
0.056 
0.056 


0.05 
0.05 
0.05 




Carbon and alloy steel f orpines. 






















0.40-O.80 
0.40-O.80 


1 
0.05a O.OVi 0.05 




Carbon and alloy steel forgings, 
annealed. 




0.05a 


0.056 0.05 








1 








0.40-o.ao 

0.40-0.80 
0.40-0.80 


0.05a 
0.05a 
0.05a 


0.056 
0.056 
0.056 


0.05 
0.05 
0.05 




Carbon and alloy steel forgings. 






untreated. 















E 
E 
E 




0.40-0.80 
0.4O-O.80 
0. 40-0. 80 


0.05a 
0.05a 
O.OSu 


0.056 


0.05 




Carbon and alloy steel forgings. 




0.056 
0% 


05 




annealed. 




0.05 












F 
P 
F 




0.40-0.80 
0.4O-Q.80 
0.4O^.iM> 


0.05a Q-CSh 


05 




Carbon and alloy steel forgings, 
annealed. 




O.OSo 
0.05a 


1 
0.056 0.05 

0.056 n 0^ 




• 










0.05 




a 




0.40-0.80 
0.40-0.80 
0.4O-O.80 


0.05a 


0.056 




Carbon and alloy steel forgings, 
quenched and tempered. 


Q 
Q 

G 




0.05a 
0.05a 
0.05a 


0.056 
0.056 
0.056 


0.05 
0.05 
0.05 





• 




0.40-0.80 










*■••■••• « 



STEEL, A. S. T. M. SPECIFICATIONS 



145 



%h9 Amarlcui Society for Testing M»teri4lg for Bteel. (Continued) 



o 



g 

s 

o 

o 



a 





ja 


] 


Diam- 


■•J 




eter 


g^^ 


J 




Str 

Ddl 

inci 


•li-s 




o 


b 


9 




,^ij 


«) 


o 


i^« 


•S o b 


> 


o fl 


•2^8 


O 


H^ 


^♦>a 


^*»ft 






d g 0) 



Reduction of 
area, per cent 



go 
a. 85 



4 

7 

10 



4 

7 

10 

ao 



all 

si 



12 

I 
12, 20 



..; 12 
12' 20 



■] 



8 
12 



8 
12 
20 



8 



8 
12 



12 20 



8 
12 



8 
12 
20 



4 
4 7 

7I 10 
10' 20 



90 
85 
85 
82.5 



47-60 

60 

60 



60 
60 



75 
75 
75 



75 
75 
75 



80 
80 
80 



90 
85 
85 
82.5 



55 
50 
50 
46 



0.5T.8. 
0.5 T. S. 
0.5 T. 8. 



Z100.000 _ . 

iiob'ooo 

T S " 
1.900.000 

T.S. ' 
1300.000 

T.S. 



0.5 T.S. 
0.5 T.S. 



1.500.000 

T.S. 
1.550.000 

T S 
1.480.600 

T.S. 



0.5 T.S. 
0.5 T.S. 
0.5 T.S. 



0.5 T. S. 
0.5 T.S. 
0.5 T.S. 



1700.000 

T.S. 
1^00.000 

T.S. 

1.600.000 

T S 

i.5o6"6oo 

T S 

i.4ob'.d oo 
T.sT 



0.5 T.S. 
0.5 T.S. 
0.5 T.S. 



55 
50 
50 
48 



h8qq.ooo 

]725.600 

T~S 
1^50.000 

T.S. 



K800.oqo 
tTs. 

1.725.000 

T S 
I>5b.000 

T.S. 



2jqa8oo 

T 8 
2.000.000 

T S 

KWb.doq 

T S 
1.800.000 

T.S. 



20.5 
19.5 
19 



22 
21 



25 

24 



18 
17 
16 



20 
19 
18 



20 
19 

18 



20.5 
20.5 
19.5 
19 



4^.000 

T S. 
3^Od!000 

T 8 
3^600^ 

T 8 
3.400.000 

T.S. 



2JOO.000 

T.S. 
Z400.000 

T.S. 
2.220.000 

T.S. 



2.700.000 

T S 
2320.6 00 

T.S. 



2.200 . 000 

T.S. 
2.000. 000 

T S 
I.8OO.6 0O 

T.S. 



2.800. 000 

T S 
2.640.00 

T S 
2.400.600 

T.S. 



2.800.000 
T S 

2.64'a6oo 

T.S. 
2^00.000 

T.S. 



4.000.000 

T S 
3^00.600 

T S 
3.600.000 

T S 
3.400.600 

T.S. 



B 

a 

a 



39 
39 
37 
36 



35 
32 



38 
36 



24 
22 
20 



33 
31 
29 



32 

30 
28 



39 
39 
37 
36 



10 



146 



IRON AND STEEL 



Table 89. Gondented Ch«mio«l and Physical Requirements of 



Material 



S 








9 


9 








8 


kt 








s 




M 


3 


a 




M 


0> 


^ 







Man 


S 


ulp 


.S 




CU 


' GO 


GC 



Carbon and alloy steel forginge, 
annealed. 



Carbon and alloy steel forgings, 
quenched and tempered. 



H 
H 



Chrome-vanadium. . , 
or ohrome-nickel. . 
or chromium-eteel. 



Steel castings 

Steel castings, hard. 



Steel caatings, medium. 
^teel castings, soft. . . . , 



1 
I 
I 
I 



:0.40-0.80 



0.40-0.80 



0.04a 



0.04b 



0.04a 0.046 



0.05 
0.05 



K 



0.40-0.80 ;0.04a :0.04& 

0.40-0.80 |0.04a 0.046 

I I 

0.4O-0.80 0.04a 0.046 



0.05 
0.05 
0.05 



iO.40-0.80 0.04a 0.046 0.05 



0.28-0.42 0.40-0.70 



0.28-0.42 



0.28-0.42 



A 
B 



0.30 max. 



Cold rolled steel axles. 



Chrome-vanadium. . , 
or chrome-nickel. . 
or chromium-steel. 



O.OSa 



0.40^.70 



0.40-0.70 



0.40 max. 



0.40 max. 
0.40 max. 
0.40 max. 



Chrome- vanadium . 



or chrome-nickel steel 



M 



0.046 



0.05a 



0.05a 



0.06 
0.05 

0.05 

0.05 



0.046 



0.046 



0.4O-O.80 0.05 



0.40-0.80 
0.40-0.80 
0.40^.80 



0.35-0.50 



0.35-0.50 



0.05 
0.05 
0.05 



0.05 



0.05 



0.05 



0.05 
0.05 
0.05 



0.05 



0.50-0.90 



0.04 



0.05 
0.05 
0.05 



0.05 



0.50-0.90 0.04 ! 0.05 



In this table, the letters "a." "b," and "T.S." respectively represent "acid steel/' 
"basic steel," and "tensile strength." 

Under "blooms, billets and slabs for carbon steel forgings," the classification la u 
follows: — 

Class A, for welding and case hardening. 

Class B, for case hardening when subeequently treated. 

Class C, for special purposes. 

Class D, axles, shafts, connecting rods and similar forgings. 

Class E, for Class D forgings when they are to be heat treated. 

Under "carbon and alloy steel forgings," the classification is as fdlowi: 

Class A, forgings which may be welded or case hardened. 



STEEL, A, S. T. Af. SPBCIFICATIO.KS 



147 



the American Society for Testing Materials for Steel. (Continued) 





a 

O 

ki 
JS 

O 


a 

•«■ 

•s 
s 

> 


Diam- 
eter 


Tensile 
strength, 
thousand Ib*- 
per sq. in. 


Yield point, 
thousand lbs 
per sq. in. 


Elongation 
in 8 in., 
per cent 


Elongation 
in 2 in., 
per cent 


Reduction of 
area, per cent 




> 
O 


1 




a 

6 

:§ 
IS 


3.00 
3.08 


1 




• • 

12 

  

4 

7 

10 

 • 

2 

4 

7 

10 


12 
20 


80 
80 


50 
50 


2.000.000 

T S 
1,900.000 

T.S. 


22 
21 


3.600.000 

T.S. 
3.400.000 

T.S. 


40 
38 








3.00 






4 

7 

10 

20 


100 

100 

90 

85 


70 
65 
60 
55 


2.200.000 

T.S. 
2.100.000 

T.S. 
2.000.000 

T S 
1.900.000 

T.S. 


20 
20 
20 
20 


4.500.000 
T *^ 

4.3ob!doo 

T.S. 
4.100.000 

T S 

3.900000 

TS. 


41 


3.00 




41 


3.00 






41 


3.00 


1 




41 










0.75-1.25 
6!70inin. 
6.60^.96 


0.15 min. 


2 

4 

7 

10 

20 


95-115 
90-110 
90-110 
90-110 
85-105 


70 
65 
65 
65 
60 




20 

20 
20 
20 
20 


• 




50 
SO 


1.25 min. 




50 
50 






50 






• • 

• • 

 • 


* oo"" 

70 
60 


"6.45" 
T.S. 
0.45 
T.S. 
0.45 
T.S. 




18 
22 







^ 




1 


• • 

• • 

• • 

•  

2 

4 

7 

10 

» ft 

2 

4 

7 

10 


20 
25 
30 








• • 


70 


60 




18 


• 


35 










0.75-1,25 
0.70 min. 
0.60-0.90 


0.15 min. 


2 

4 

7 

10 

20 


105-125 
100-120 
100-120 
100-120 
95-115 


80 
75 
75 
75 
70 




18 
18 
18 
18 
18 




1 35 


l.2> nun. 


35 
1 35 






45 
45 








0.75-1.25 
0.70 min. 


0.15 min. 


2 

4 

7 

10 

20 


125 
115 
110 
110 
110 


105 
95 
85 
75 
70 




16 
16 
16 
18 
18 


1 


50 


. • • . • 
2.75 min. 


45 

45 

45 

1 45 



Class B. mild steel forgings for structural purposes, for minor ship fittings, etc. 

Class C. mild steel forgings for structural purposes, for ships, etc. 

Classes D to I, various maohinery forgings, choice depending on design and upon the 
skesses and servioes to be imposed. 

Class K, L and M. various machinery forgings, including quenched and tempered 
ailes, shafts and other forcings, choice depending on design, on the stresses and services 
to be imposed, and on the oharaeter of the machining to be done. 

Under "steel castings*'* Class A includes ordinary castings for which no physical re- 
quirements are specified; Class B includes castings for which physical requirements are 
specified. 



148 



IRON AND STBBL 



Samples for Selective Test, see carbon tool steel, except that dimensions 
of sample bars shall be as follows: 
Class 1, H by 1 inch by 6 feet long. 
Class 2, 1 K 6 inch diameter rod, 2}^ feet long. 
Treatment of Sample, see carbon tool steel. 

Selective Tests. Clciss 1. The sample bar will be cut into five sections, 
one end of each section treated and ground to the No. 30 form of the Sellers 
system of lathe tools. Each tool will be tested on a nickel-steel forging of 
about 100,(X)0 lbs. tensile strength, with a cut ^{e in. deep, 0.044-in. feed, and 
a cutting speed of about 66 ft. per min. Each tool will be once reground and 
again tested. A record will be made of the length of time each tool cuts 
without a lubricant befoie it is ruined. 

Class 2. Five ^f 6 in. diam. 4- tooth facing mills will be made from the 
sample rod and tested on a piece of ^-in. ship*s plate without lubricant. 
Each mill will be run until it is so dull that it breaks either in the teeth or in 
the shank. The depth of cut will be 0.08 in., the revolutions per minute of 
the mill will be 370, and the feed of material 20 in. i)er min. A record will be 
made of the length of time each mill operates. 

U. S. NAVT SPECIFICATIONS FOB CAST IRON (ABSTRACTS) 

Foundry Pig Iron (1917) 

Uses and Grades. There shall be four grades of pig iron as follows: 

(a) Grade 1 is suitable for general foundry purposes. It may be used for 
either hea^'y or light castings which are to be machined. 

(b) Grade 2 is suitable for marine engine cylinders, turbine casings, and 
work of similar character. 

(c) Grade 3 is suitable for hard, close-grained castings, which are to 
be machined, where great strength is required. It may also be used with 
grades 1 and 2 in varying proix>rtions as the work requires. 

(d) Grade 4 is suitable for use with grades 1, 2, and 3 ^here castings of 
great strength or high finish are desired. 

Chemical properties are required as follows: 



Grade 


Carbon, 
(mini- 
mum) 

per cent 

3.50 
3.25 
3.25 
3.25 


Silicon, 
per cent 


Sulphur, 
(maxi- 
mum) 

per cent 


Phos- 
phorus, 
per cent 


Man- 
ganese, 
per cent 

0.50-0.90 
0.50-0.90 
0.5(M).90 
0.75-1.25 


Remarks 


No. 1 

No. 2 

No. :? 

No. 4 


2.75-3.25 
2.00-2.50 
1.25-1.75 
1.50-2.00 


0.04 
0.05 
0.06 
0.03 


0.50-0.80 
0.50-0.80 
0.50-O.90 
0.30 max. 


Charcoal iron. 



The sample shall be taken as follows: (a) One pig shall be taken for every 
four tons in the lot, chosen from different locations so as to represent as nearly 
as possible the average quality of the lot. A lot shall always consist of 
pig from the same heat, no mixing of iron from several heats being permissible. 

(h) The pigs selected for test shall be broken so as to present a clean fract- 
ure over the entire cross-section of the pig. One-half of each pig shall have 
drillings taken from 3 points triangularly spaced on the clean part of the 
fracture. Equal proportion of drillings from each pig shall be thorov^fchly 
mixed and analysis made from this sample; no resampling will be permitted. 

Method of Sampling. Not less than 6 ounces of the sample, taken and 
mixed as above, is used for analyses. In case the first analysis shows that 



CAST IRON, U. S, NAVY SPECIFICATIONS 



149 



I 



the material does not conform to the specifioatlonB a oheok analysis shall be 
made. The average of these analyses shall be considered final. Analyses 
shall be made according to the standard method of the American Foundry- 
men's .Association, the gravimetric method being used for determination of 
sulphur. Other things being equal, preference will be given to machine 
east over sand oast iron. 

Sow Iron. Not more than 12 per cent of sow iron is acceptable. 

Iron CMtlngs (1916) 

PhjriieAl proportioi of cast iron are to be in accordance ¥rith the follow- 
ing table : 



Grades 
of iron 

CMt- 

iagi 



2 



a 

4 



Tensile strength 
(pounds per 

square inch) — 
length of test 
niece not less 
than 2 inches 



20.000 (min.) 



20p000 (min ) 



90,000 (min.r 



Transverse break- 
ing load (for bar 
1 inch square 
loaded at mid- 
dle and resting 
on supports 1 
foot apart) 



2.20 ) (min.) 
2.800 (max.) 



2,500 (min.) 



2,200 (min.) 



Purposes for which intended 



To be inspected to see if they are in all 
respects suitable for the purposes for 
which they are intended. 



Steam cylinder and valve-chest cas- 
ings. 

Steam turbine casings, steam turbine 
parts. 

Gas-engine cylinder and valve-chest 
casings. 

Intemal-oombustion engine cylinders 
and valve-chest casings. 

Cylinder liners and valve-chest liners. 

Steam, gas. and internal combustion 
engines. 

Cylinder and valve-chest linen, small 
gas engines, and internal-combus- 
tion cylinders when cast in one 
piece. 

Other important parts, such ss main 
and auxiliary engine parts, etc. 

Minor parts, such as furnace fittings, 
etc. 



BirdnoiS Roqniromont. Great care must be taken to determine that 
the machinery specifications for hardness of cylinders. liners, and valve- 
ehest liners are complied with, and a test piece from the casting should be 
machined in order to show the degree of hardness. 

Quality of Matorigl. The castings must be of uniform grain, smooth, 
free from blow-holes, porous places, shrinkage, and other cracks or defectsi 
ftnd must be well cleaned. 

Humbar of Tegtg. Sound test pieces shall be taken in sufficient number 
to exhibit the character of the metal in the entire piece from all castings 
requiring physioal test. 

Iniih. Scale must be removed from unfinished parts of the insides of 
all cylinders, cylinder covers, valve-chest covers and cylinder and valve- 
chest liners, and from ports and passages of cylinders and valve-chests, 
cither by pickling or other approved process as may be required. 

AH engine castings must be finished to blue-print sise. 



150 IRON AND STEEL 

Malleable Iron Caitingi (1917) 

Workmanship and Finish. The castings shall be free from blemishes, 
scale and shrinkage cracks and shall substantially conform to the sizes and 
shapes of the patterns. A variation of ^^2 ^^' P®^ ^^' ^ permitted. 

ProoeSB. The castings shall be made from iron melted in either an air 
furnace, open-hearth furnace or electric furnace. 

Chemical and Physical Requirements. Limiting percentage of 
sulphur is 0.10 (max.) and of phosphorous is 0.23 (max.); minimum tensile 
strength, 38,000 lbs. per sq. in.; elongation in 2 in., 5 per cent. The tensile 
test specimen is shown in Fig. 15. 

The transverse test specimen, hereafter described, when tested with the 
cope side up on supports 12 in. apart, with pressure applied at the center, 
shall conform to the following requirements as to transverse properties: 



ThicknoM of specimen, m \ 

Minimum load applied at center, lbs i 

Minimum deflection at center, lbs I 



H 


900 


1.25 


H 


1400 


1.00 


?< 


2000 


0.75 



Transverse test specimens shall be 14 in. in length by 1 in. in width, * 
and either }^ in., ^ in., or ^^ in., in thickness. The thickness of the speci- 
men selected shall be in proportion to the thickness of the casting which it 
represents. 

Two tension and two transverse test specimens shall be cast in each mold 
with risers of sufficient height at each end to secure sound bars. All speci- 
mens shall be cast without chills and with ends periectly free in the mold. 

Four molds shall be poured to represent each melt. When the entire 
melt is used for castings which are subject to these specifications two molds 
shall be poured within 5 minutes after tapping into the first ladle, and two 
molds from the last iron of the melt. When only part of the melt is required 
for such castings two molds shall be poured from the first ladle of iron used 
and two molds after the required iron has been tapped. 

The test specimens from one mold from the first and oife mold from the 
last of the melt shall be annealed in the hottest part of the annealing oven 
and the remaining specimens shall be annealed in the coldest part. 

▲. 8. T. M. 8PKCIFXCATION8 FOR CA8T IKON (AB8T&ACT8) 

Malleable Iron Casting! (1915) 

Physical and Chemical Requirements. The castings shall be made from iron 
melted in either an air furnace, open hearth furnace or electric furnace. 

Tension test specimens, Fig. 14, shall conform to the following minimum requirements 
as to tensile properties: 

Tensile strength, lbs. per sq. in 38,000 

Elongation in 2 in., per cent 5 

Transverse test spc»oimens, tested with the cope side up oA supports 12 in. apart, 
pressure being applied at the oetitcr, shall conform to the following requirements as to 
transverse properties: 



Thickness of specimen, 
in. 


Minimum load Aliuimum deflection 
applied at center, lbs. 1 at center, in. 


1: 


900 
1400 
2000 


1.25 
1.00 
0.75 



CAST tttON, A. S. T. .V. SPECIFICATIONS 161 

1e addition to tiu lenuoo ud truuvsne t«b^ tha ingpector rEprsMntins the pur- 
tiatet ouy utialy himself of the BuiUbility of the iroc uaed for Ihe cudasi by brmk- 
inc L rrvBODflble nurabvr of ctutioe" bfltor« nnaeiUinff Id eiamiiie for ercesaive mottlixME 
or grapbite epotA. In the okAe of cutinc" of BpeciAl drsiffa or importiLiicF, he mny nbo 
nqmrfi tevt iup of » dse proportioQal to the tbickneei of the cutiof. but rxot eroeedioc 
K by H IB- in eection. At lu«t one of tbeK luo ghsU be left on the outins (or Qui 



3W. 



Tart Ipselinaai. (a| TensoD t« 
■liown in Flc. 1£, Tntnerena leit ip- 
«d either M. M or « in. in thiekne, 



riwTS o( mS 


clFDt 


hei«ht It 


eaoh 


end to K4 


ure 


sound ban. 


All ipedim 


eos .hall bo 


«M without 


ebai. 


and with 


nd« perfectly ( 




the mold. 






(() Four molds 


.haU b. p. 


urrd 






aeh mrlt. 


When the enlire melt is 




ngii whiih ire s 


uhj« 








o molda iha 




-ithin five m 


nute 


e mfter tmp 


ing 


olo the finrt la. 


die. and two 


molds from 


the last iroD 


df t>H melt. 


Whe 




of the melt « 




red tor euoh 


eastinn, two molda gball 


beponredfn 






ntueduid 




molds after 


he required 


ronhaabooD 


tapped. 


















(J) Them 


old. 


heUbesuit 


nbly 


tamped t 


ide. 


Dtify the >pe 


:ilDen.. 






shall be annealed in the hottest part of I 
kDoealed in the coldest part- 



152 IRON ASD STEBL 

Workmuuhlp. The nutino ihall lubelUDtildly conform to the riica ftnd (him 
of the ptlterm, iLaiJ tbiii be mule in  workmulike muiner. A varutian of Hi ii 
per It. will be perrnitled. 

The eutioca ahiU be tree from blemithn, HiUe und ghrinkaie ettcka. 

Orkr-lTDu Cutin(i (leoS) 
UnleH fuTQBce iron ia specified, ^1 v^V cmUd^ ve uodenlood Ut be made by It 
Ohnnloal PToiMrtlM. The aulphur contenta to be u (ollowa: 

Ucbt cutiuca Not over O.OS per oeiil 

Medium CMtion,,. Not over 0, 10 per oent 

He«T7 eMtina Not over O.ia per oent 





J 



foUa« 









a into light, madjum ukd heavy -' . the 



CvtinKi having any section leai than K-in- thicli ahall be known u lipAl cattinft. 

Caatinia in which □□ section is leas than 3 in. thick shall be known as kauv cattinai. 

Utiium oattirv are those not Inoluded in the above ctaasBcation. 

PhTiiol Frop<rtlM. TraniHru TuL The mlnimiun breakinc stnnsth of the 
"Arbitration Bar" under transverse load shall be not under 3,A00 lbs. for light; 2,000 
Ibe. tor medium and 3.300 lbs. for heavy castings. In no case shall the deflection be 
under 0.10 inch. TntU» Tttl: Where speciaed. this shall not run loM than IS.ODD Ibe. 
per M. in. (or light; 31,000 lbs. tor mediutn; and 34.000 lbs. for heavy Dasting). 

Arblb^tton Bar. The quality of the iron gc^ng into castings under speoiflca- 

1d diameter and IS in. long. It ehall be prepared as stated further on and teeted tnuru' 
varsely. The tensile teat it not recommended, but is case It it called for, the bar ■• ',, 



PROTECTIVE COATINGS FOR IRON AND STEEL 153 

ahawa in Fie. 15, and turned up from any of the broken pieoes of the transverse test 
shall be used. The expense of the tensile test shall fall on the purchaser. 

Hnmbsr of Tfl«t Ban. Two sets of two bars shall be cast from each heat, one set 
from the first and the other set from the last iron going into the castings. Where 
the heat exceeds twenty tons, an additional set of two bars shall be cast for each twenty 
tons or fraction thereof above this amount. In case of a change of mixture during the 
heat, one set of two bars shall also be cast for every mixture other than the regular one. 
Esch set of two bars is to go into a single mold. The bars shall not be rumbled or 
othenHse treated, being simply brnsfaed off b^cve testing. 

Vflthod of TMting. The transverse test shall be made on all the bars oast^ with 
supports 12 in. apart, load applied at the middle, and the deflection at rupture noted. 
One bar of every two of each set made m\ist fulfill the requirements to permit acceptance 
of the ftintings represented. 

Moid for Tost Bar. The mold for the bars is shown in Hg. Id. The bottom of 
the bar is Hs in. smaller in diameter than the top, to allow for draft and for the strain 
of pouring. The pattern shall not be rapped before withdrawing. The flask is to be 
rsmmed up with green molding sand, a little damper than usual, well mixed and put 
through a No. 8 sieve, with a mixture of one to twelve bituminous facing. The mold 
shall be rammed evenly and fairly hard, thoroughly dried and not cast until it te oold. 
The test bar shall not be removed from the mold until oold enough to be handled. 

Speed of Tooting. The rate of application of the load shall be from 20 to 40 seeonds 
for a deflection of 0.10 in. 

Samples for Analyils. Borings from the broken pieoes of the * 'Arbitration Bar'' 
ihsll be used for the sulphw* determinations. One determination for eaoh mold made 
■hsU be required. In ease of dispute, the standards of the American Foundry men's 
Association shall be used for comparison. 

flnlob. CastincB shall be true to pattern, free from cracks, flaws and exoessive 
shrinkage. In other respeota they shall conform to whatever points may be specially 
sgreed upon. 

PftOTSCTIVI COATIHQS rOB IRON AND 8TBXL 

Protective coatii&gB are of three types : BC^tallle coatinct ; coatings formed 
by ggidatlon or other ohemical change of the surface of the iron; 
ergaaie coatingi such as paints, varnishes, enamels etc. 

Metallic Goatings. These may include any of the common metals and 
alloy's that can be readily applied to steel. A list of these metals, together 
with iron, arranged in the order of their electric potentials is as follows: 
Aluminum, zinc, iron, cobalt, nickel, tin, lead, copper, silver. The relative 
solution tensions of these metals are such that any metal can displace a 
metal following it in the list from solutions of its salts. Consequently, when 
these two metals are in contact, the first metal protects the second from 
corrosion. 

Of the metals in the above list, therefore, only two protect iron by their 
chemical action. Of these two, zinc is the more generally useful on account 
of its low cost and ease of application. Since zinc protects iron by its electa 
rochemical action, a hole or flaw in the coating does not lead to corrosion 
of the iron unless the uncovered area is so large that the protective influence 
of the sine does not extend to all parts. 

The oldest and most generally useful method of applsring the zinc coating 
ia hot dipping. In this process, the steel aft«r a preliminary cleaning of the 
surface is immersed in molten zinc. 

Another process, called "therardiaing," consists in subjecting the iron 
to an atmusphere of zinc vapor. The iron is packed in a revolving drum with 
zinc dust containing a small amount of zinc oxide; it is then heated at a 
temperature of 550 to 375 deg. C. for 3^ to 4 hours. 



154 JnON AND STEEL 

Zinc 1^ also applied hy eleotroplatinf . The plating liquid is either a 
zinc sulphate solution containing a little free acid, or a solution of the cyanide 
or oxide in a mixture of sodium cyanide and sodium hydroxide. Plating 
usually takes from }^ to 1 hour unless very heavy deposits are required. 

In the Schoop proc688» zinc or other metal in the form of wire is fed into 
a spray gun where it is melted in an oxyacetylene flame and projected by a 
strong air current against the object to be plated. 

In another process, called "epicassit," the zinc in the form of filings is 
mixed with flux, made into a paste and painted on the steel; the steel is then 
heated until the zinc melts and forms a continuous coating. 

Of these methods each has its advantages and disadvantages. Since 
zinc applied by the hot dipping method collects in depressions and re-entrant 
angles, this method is not as suitable as the sherardizing method for protoot- 
ing accurately machined surfaces such as screw threads. Although good 
protection may be obtained by use of the sheradizing process, this process 
gives a less uniform product than does the hot dipping process; the lack of 
uniformity is due to the fact that the quality of the product is much influenced 
by variations in the purity of the zinc dust, in the uniformity of heating, and 
in other conditions. Neither the hot dipping nor the sherardizing methods 
are suitable for use on hardened steel or any other metal that would be un- 
favorably affected by the temperatures prevailing in these processes. For 
such material, the electroplating or the Schoop processes are suitable. An- 
other advantage of the electroplating process is the ease with which the thick- 
ness of the coating can be controlled. The thickness on sharp projections, 
however, is greater than on depressions even on flat plates, the coating is 
somewhat heavier at the edges Uian near the center. 

Aluminum, since it costs more and is less easily applied, it less useful 
than zinc as a protective coating. One method of application, called 
"calorixingi" is similar to sherardizing. The steel tol?e calorized is packed 
in a mixture of aluminum, aluminum oxide, and ammonium chloride; it is 
then heated to about 900 deg. C. for 2 of 3 hours. The absorbed aluminum 
vapor forms an alloy with the iron. 

Though the calorizing process does not prevent corrosion at ordinary 
temperatures, it increases the resistance of steel to oxidation at high temper- 
atures. It is claimed that this process protects steel indefinitely from 
oxidation at temperatures up to 1060 deg. C. and greatly increases the life 
of steel objects at still higher temperatures. The protection is due to a film 
of aluminum oxide on the surface of the calorized object. 

Protective metals other than zinc and aluminum may be divided into two 
groups. In the one group are metals of low melting point, such as tin, 
lead, and their alloys; in the other group are the metala of high meltlnir 
point, such as copper, nickel, cobalt, silver, and their alloys. Metals of the 
first group are usually applied by hot dipping; metals of the second group and 
some of the metals of the first group are applied by electroplating. 

Tin as a metallic coating is widely used. Unless the coating is free from 
pin holes or abrasions, the iron in these regions will be corroded more rapidly 
than if no tin coating were present. Since, however, tin corrodes only slo'wly, 
the coating, when intact, affords efficient protection. 

Since lead is much cheaper than tin, it is frequently used in ooatinsB aa 
and alloy with tin. Such an alloy, known as tcma, contains about ^ lead 
and H tin. Recently lead alone applied by electroplating, has been much 
used. 

Though copper is usually deposited by electroplating, it may also be 



PBOTBCTIVJB COATINGS FOR IRON AND STEEL 166 

applied by the Schoop and epicaesit processes. Copper elad steel is pro- 
duced by casting the copper around a steel billet and rolling this down into 
rods or ^eets. The coating thus formed is very efficient. 

Nickel is usually applied by electroplating. Niokel olad tteel is also in 
use; it is made by a process similar to that used in manufacture of copper olad 
steel. 

Cobalt coatings are bluish white in color. They have the same uses as 
nickel coatings. Cobalt is applied by electroplating. Since solutions for 
cobalt plating cian be made much more concentrated than those for nickel 
plating, it is possible to use a much greater current density in the deposition 
of cobalt than in the deposition of nickel. For this reason, cobalt can be 
deposited from its solutions from 4 to 15 times as fast as niokel. On account 
of its much greater hardness, cobalt coating is equal in protective power to 
nickel coating 4 times as thick. Although the cost of cobalt is greater than 
that of nickel, the higher cost is offset by the reduced quantity required and 
the greater speed of deposition. 

BraM coatings are deposited by electroplating from a solution containing 
both copper and sine. Aside from its color, wl^ch is considered desirable 
for small ornamental fixtures, brass has no advantages over either copper or 
sine as a coating. Brass and bronse have also been applied by a process 
similar to the copper clad process. 

Microetracture of metallic coatings. Metals applied by hot dip- 
ping usually form alloys with the iron. The coating thus formed, therefore, 
consists of one or more layers of alloy adjacent to the iron, also an exterior 
layer of the protective metal alone. Metals applied by sherardizing and 
similar processes also form alloys with the iron. The coating, in this case, 
contains one or more layers of iron alloy and an exterior layer of protective 
metal, which is thinner than on hot dipped objects. The iron alloys appear 
to be definite compounds. Since some of these compounds have electric 
potentials that are not intermediate between the potentials of their consti- 
tuent elements, the protective qualities of the coating may vary considerably . 
with the proportion of alloy in the coating. Coatings deposited by electro- 
plating contain no layers of iron alloy. The coatings consist of crystals 
elongated in a direction i>erpendicular to the surface of the iron. Coatings 
deposited by the Schoop process also show no layer of iron alloy; they are 
chiefly mechanical conglomerates of the sprayed drops of metal. 

Methods of Testing Metallic Coatings. The ueual methods of testing linc 
coatings are the Preece test, the basic lead acetate test, the hjrdroohloric acid-antimony 
chloride test, and the salt spray test. 

Id the Fleece test, the carefully cleaned sample u dipped in a solution of copper 
Bulphate, held in the solution for one minute, washed, and lightly rubbed to remove 
deposited copper. The solution is made by dissolving 36 parts commercial copper 
sulphate in 100 parts water, adding some cupric oxide to neutralise any free acid, 
then dilutillg with water until the specific gravity is 1.186 at 18 deg. C, at about which 
teaiperature the solution should be used. 

As long as sine remains on the surface, the copper deposited on it is loosely adherent; 
ss soon as the siao eoaiing has been removed from any part of the surface, however, 
there appears at that point a deposit of bright, adherent copper. The number of dips 
necessary so reach this end point are an index of the effectiveness of the coating. The 
Preece method, therefore, is used to determine the effectiveness of a coating at its 
thinnest point. Since the Iron-sine alloys are not readily removed by this method, 
the Preece test gives sueh variable results; especiaMy in testing sherardised objeots, 
that the A.S.T.M. Committee on Corrosion has recommended its* abandonment. 



156 IRON AND STBBL 

The bMto l««d Metata tost is used to determine the weight of sine coating per unit 
of surface area. The solution is made by dissolving 400 gm. crystallised lead acetate 
in one liter of water, adding 4 gm. powdered litharge, shaking and filtering; the solution 
is then diluted until its specific gravity is 1.275 at 15.5 deg. C. In this solution, the 
weighed specimens are given successive immersions of about three minates each, fol- 
lowed each time by brushing, until a bright iron surface is ezpoeed. The specimens are 
then washed, dried, and reweighed. Since this method removes not only the pure sine 
but also the sinc^iron alloys, it may be used to determine the total weight of coating 
on sherardised as well as on hot dipped objects. 

The hjrdrochloiie •ctd-antJTnonj chloride tMt like the basic, lead acetate 
method, is used to determine the total weight of sine coating per unit of surface area. 
The weighed specimens, whose total surface area should be not less than about four 
square inches, are dipped in a solution containing 100 c.c. concentrated hydrochloric 
acid to which has been added 5 c.o. of a solution of antimony triozide in one liter of 
conoentrated hydrochloric acid. The same solution may be used five times, if before 
each immersion 5 c.c. additional antimony chloride solution are added. The samples, 
after immersion for one minute, are brushed, rinsed in nmning water, and reweighed 
if the removal of the coating has beeii complete. 

Immersion for one minute for hot dipped objecte and four minutes for sherardised 
objects is usually sufficient. The antimony deposited on the iron protecte it from solu- 
tion, whUe not interfering with the s<^ution of the sine. The loas in weight, therefore, 
equals the weight of the sine coating. 

The salt spray method, which has been growing in favor recently, tests the endur- 
ance of a coating under accelerated service conditions. In this method, the specimens 
are ezpoeed to a fog of fine particles of a saturated salt solution. The fog is produced 
by sprasring the salt solution through an ordinary atomiser by means of an air Mast; 
the specimens are so supported that the spray from the atomiser does not strike them 
directly. The removal of the coating is usually indicated by the appearance of iron 
rust on the regions where the coating was least effective. Hn holes may thus be de- 
tected in from three to ten hours. If the sample shows failure of the coating in less than 
24 hours, it should be regarded as unsatisfactory. Endurance for two or three days 
indicates a coating that would endure under moderate service oonditions, while endur- 
anoo for four to six days indicates a ooating that would endure under severe serviee 
conditions. 

Flaws In eoatlngs of lead, tin, c o ppr ate. may be detected by various color 
reactions. One of the best reagento for this purpose is a one per cent solution .of soditun 
ferri-eyanide in two per cent sulphuric acid. With this reagent, the appearance of a 
blue percipitate on any part of the coating indicates exposed iron. 

Protection of iron by meuu of osido of Iron uBually depends on the 
formation of the magnetic oxide, FesOi. This oxide, unlike the red oxide, 
Fe<Ot, inhibits instead of accelerating corrosion. Repeated heating alter- 
nately in oxidising and reducing gases gives a comparatively heavy coating 
of this oxide. The etching and coloring processes give thinner coatinggs, 
usually of a lower order of resistance. . The oxide coatings undoubtedly 
owe some of their rust resistance to the fact that they are usually kept oiled. 

Bower-Bazft Method. In this process, the steel, is first heated at about 
350 deg. C. in air alone or in air and superheated steam. When a coating 
of ferric oxide has thus been formed, gaseous hydrocarbons are introduced 
to reduce the red oxide to the black oxide. A recent modification of this 
process consists in heating at a low red heat in a mixture of steam and bensine. 
The Swann, Bontempi, detner, and Weigelen proceises are other 
modifications of the Bower-Barff process. 

The black oxide coating may also be produced by heating the steel in 
contact with various organic mixtures, such as burnt bone and oil, burnt 
bone and charcoal, oil and sawdust, etc. Or the steel may be oiled first 
and then heated to about 350 deg. C. 



PROTECTIVE CASTINGS FOH IRON AND STEEL 157 

In the etching proceSMS, the steel after treatment with an etching solu- 
tion is allowed to dry slowly in the air. The outer coating of red oxide thus 
formed is then scraped off, leaving a thin, adherent coating of magnetic 
oxide whose color depends on the etching solution employed. The following 
list from Bureau of Standards Circular No. 80 gives some typical solutions 
and the colors thus produced. 

Color Re«gent Parts by weight. Color Reagent Parts by weight. 

Black 

First formula Second formula 

Bismuth chloride 20 Copper nitrate, 10 % solution . . . 700 

Mercuric chloride 40 Alcohol 300 

Copper chloride 20 Third formula 

Hydrochloric aoid 120 Mercurio chloride . 50 

Alcohol. 100 Ammonium chloride 50 

Water 1000 Water 1000 

Brown Brown 

first formula Second formula 

Alcohol 45 Nitric add 70 

Iron chloride solution 45 Alcohol 140 

Mrrcuic chloride . ...... 45 Copper sulphate 200 

Sweet spirits of niter. 45 Iron filings 10 

Copper sulphate 30 Water 1000 

Nitric acid 22 

Water ^ . . . . 1000 

Blue 

Iron chloride 400 

Antimony chloride 4(X) 

GslKeadd 200 

Water 1000 

Bronse 
Manganeee nitrate, 10 per cent 

solution 700 

Alcohol 300 

Similar protective coatings are produced by the action of various Other 
reftgenta. Protective oxides are produced by immersion of the steel in 
boiling alkaline solutions such as BOdiuiu hydroxide solution containing 
oxidising agents such as sodium picrate, sodium peroxide etc. Similar 
oxides are produced by the action of fused salts such as potassium nitrate, 
sodium nitrate, or a mixture of the two, sometimes containing manganese 
dioxide. A protective oxide is also formed by dipping steel in a 10 per cent 
potassium bichromate solution ttnd then heating it in a smoky flame. 
The coatings exhibiting temper colors, produced by heating steel to about 
220 to 320 deg. C, give some protection against corrosion; of these coatings, 
the blue oxide ia considered the most effective. 

The Parker or Coslett process is of wide commercial application in 
this process, the iron is immersed in hot dilute phosphoric acid containing 
ferrous and ferric phosphates or other metallic salts. The coating, when 
dried, is grayiah white in color, but becomes black when oiled. Its resistance 
to coiToeion is about the same in degree as that of the light oxide coatings. 



SCRBW THREADS. BOLTS AND .VUTS 

Tftbla 1. IT. S. (SellMi) Bt*ndftrd Boivw TlirBadi 
(For Pipe Thrskdi h> p. 12T1) 

= pitch — 1 ■!■ (No. of threads per in.) 
- depth - O.B495p 







B^P 


ll^M 


\> f 


-flat - 


p +8 














^^ 












■3i 




a 


■s . 


■33'5t3 


^i 




"^■d 


ii 


•BS'Sfl 


J! 


1.S 


ii 


lllll 


If 


Ii 


ill 


m 


t 


10 


o.iew 


00063 


0027 




4M 


.711 


o'Ta 


1.302 


!• 


la 


02«3 


00069 


o:o*5 











78 


3023 


1 






0,007* 


0068 






:i75 





3 


3 714 




14 


o:m4t 






}i 




.425 






4U0 


l' 

la 




i:S 


ii 


II 




Hi 

ii 


:a 


« 


J 


S3 


H 












.1003 


t 




54a 


S 


10 


6201 




302 


M 




.3170 




7 


HI 


9 


07W7 


0.0I» 


420 






.5670 


« 


7 


963 






a 




0156 


0.550 


M 




.7M2 


S 








7 








\i 


2H 










7 


\.VM orn 


0S95 


Ji 


>* 


4'25SI ' 0. 76 










l.tSSi 0200 


I.0S7 




M 


4.4804 DO 


















'4.7304 DO 


1 .572 






M 








H 




1 167 




H 




i:«OI 0250 


i:746 


li 


H 


5:2030 16 


] 262 




J* 


> 


I.6IU 0-02% 


2.051 






J.4226 56 





TkblB S. Whitworth StuiiUrd Screw Tbrskda 
t*-p— J 

>-A -.A d - 0.64Ct3p 

■*^^ J^ r - radius = 0.1373iJ 



' iDum. of Thruda^ 



SCREW THREADS 



150 



Tikblo 8. British Awoeiation Screw Thread! 




u 


•3. 

Jit 


Approz. 
diam., 
in. 


Pitch, 
mm. 




Diam. at 
root of 
thread, 
mm. 


1 


Diam. of 
screw, 
mm. 


Approx. 
diam., 
in. 


Pitch, 
mm. 


Apjproz. 
pitch, in. 


Diam. at 
root of 
thread, 
mm. 






0.236 


1.00 


0.0394 


4.8 




1.20 


0.047 


0.25 


0.0098 


0.90 






0.209 


0.90 


0.0354 


4.22 




1.00 


0.039 


0.23 


0.0091 


0.72 






o.ias 


0.81 


0.0319 


3.73 




0.90 


0.035 


0.21 


0.0083 


0.65 






0.161 


0.73 


0.0287 


3.22 




0.79 


0.031 


0.19 


0.0075 


0.56 






0.142 


0.66 


0.0260 


2.81 




0.70 


0.028 


0.17 


0.0067 


0.50 






0.126 


0.59 


0.0232 


2.49 




0.62 


0.024 


0.15 


0.0059 


0.44 






O.tIO 


0.53 


0.0209 


2.16 




0.54 


0.021 


0.14 


0.0055 


0.37 






0.098 


0.48 


0.0189 


1.92 


20 


0.48 


0.019 


0.12 


0.0047 


0.34 






0.067 


0.43 


0.0169 


1.68 


21 


0.42 


0017 


0.11 


0.0043 


•0.29 




1.9 


0.075 


0.39 


00154 


1.43 


22 


0.37 


0.015 


0.10 


0.0039 


0.25 


10 


1.7 


0.067 


0.35 


0.0138 


1.28 


23 


0.33 


0.013 


009 


0.0035 


0.22 


II 


1.5 


0.059 


0.31 


0.0122 


1.13 


24 


0.29 


O.OII 


O.OS 


0.0031 


0.19 


12 


1.3 


0.051 


0.28 


O.OIIO 


0.96 


25 


0.25 


0.010 


0.07 


0.0028 


0.17 



A. S. BflL X. Standard Screw Threads follow the U. S. Standard form 
except that the proportions are as follows: 

d = 0.7037 p; / (top) = p 4- 8; / (bottom) « p + 16 



Table 4. French (Metric) Standard Screw Threads 



p = pitch in mm. 
d « 0.6495p 
/-P -s-8 




 

a 
^a 


• 


troot 
ad. 


i 


• 

a 


t 

a 

mm 


«3 



- 


1 

"2 


• 

a 
^a 


 

a 
a 

1 


t root 
ad. 


i 


. 

5- ^ 


s 




O 


o . 


a 

i 


4 I 





11 


pa 
^'sa 




H 

ga 


3 


0.5 


2.35 0.06 


18 


2.5 


14.75 


0.31 


40 


4.0 


34.800.50 


4 


0.75 


3.03 


0.09 


20 


25 


16.75 


0.31 


42 


4.5 


36.15 


0.56 


5 


0.75 


4.03 


0.09 


22 


2 5 


18.75 


0.31 


44 


4.5 


38.15 


0.56 


6 


1.0 


4.70 


0.13 


22 


3 


18.10 


0.38 


45 


4.5 


39.15 


0.56 


7 


1.0 


5.700.13 


24 


3.0 


20.10 


0.38 


46 


4.5 


40.15 


0.56 


8 


1.0 


6.70 0.13 


26 


3.0 


22.10 


0.38 


48 


5.0 


41.51 


0.63 


6 


1.25 


6.38 0.16 


27 


3.0 


23.10 


0.38 


50 


50 


43.51 


0.63 


9 


1.0 


7.70 0.13 


28 


3.0 


24.10 


0.38 


52 


5.0 


45.51 


0.63 


9 


1.25 


7.38 0.16 


30 


3.5 


25.45 


0.44 


56 


5.5 


48.86 


0.69 


ro 


1.5 


8.05 


0.19 


32 


3.5 


27.45 


0.44 


60 


5.5 


52.86 


0.69 


11 


1.5 


9.05 


0.19 


33 


3.5 


28.45 


0.44 


64 


6.0 


56.21 


0.75 


12 


1.5 


10.05 


0.19 


34 


3.5 


29.45 


0.44 


68 


6.0 


60.21 


0,75 


12 


1.75 


9.73 


0.22 


36 


4.0 


30.80 0.5 


72 


6.5 


63.56 0.81 


14 


2.0 


11.40 


0.25 


18 


4.0 


32.60 0.5 


76 


6.5 


67.56 


0.81 


16 


2.0 


13.40 


0.25 


39 


4.0 


33.80 


0.5 


80 


7.0 


70.91 


0.88 



160 



SCREW THREADS, BOLTS AND NUTS 



Tftble 5. International Standard Metric Screw 




=; — «-*• 

' i rf « 0.7036p 
t = 0.866j> 



k— ^— >l 



•M 




<M 




<M 








«M 




«»* 




o . 




o . 




o , 




•s . 




o . 




o . 




•S ^ S 


Pitch, 
mm. 


Diam. 

screw 
mm. 


Pitch, 
mm. 


Diam. 
screw 
mm. 


Pitch, 
mm. 


Diam 
screw 
mm. 


Pitch, 
mm. 


Diam. 
screw 
mm. 


Pitch, 
mm. 


Diam. 
■crew 
mm. 


Pitch, 
mm. 


6 


1.00 


12 


1.75 


24 


3.00 


42 


4.50 


64 


6.00 


96 


8.00 


7 


1.00 


14 


2.00 


27 


3.00 


45 


4.50 


68 


6.00 


116 


9.00 


6 


1.25 


16 


200 


30 


3.50 


48 


5.00 


72 


6.50 


136 


10.00 


9 


1.25 


18 


2.50 


33 


3.50 


52 


5.00 


76 


6.50 






10 


1.50 


20 


2.50 


36 


4.00 


56 


5.50 


80 


7.00 






II 


1.50 


22 


2.50 


39 


4.00 


60 


5.50 


88 


7.50 







Table S. Acme 29'deg. Screw Threads 







d = 0.5p + 0.01 in. 

F «0.3707p 

H = 0.3707p - 0.00.52 in. 



N 


p 


d 


F 


W 


.S 


B 


Number of 
threads 
per in. 


Pitch of 

sinslo 

thread, in. 


Depth of 

thread, 

in. 


Width of 

top of 
thread, in. 


Width of 

space at 

bottom of 

thread, in. 


Width of 

space at 

top of 

thread, in. 


ThiokneM 

at root 

of thread. 

in. 


1 


1.0 


0.5100 


0,3707 


0.3655 


0.6293 


0.6345 


m 


0.750 


0.3850 


0.2780 


0.2728 


0.4720 


0.4772 




0.500 


0.2600 


0.1853 


0.1801 


0.3147 


0.3499 




0.3333 


0.1767 


0.1235 


0.1183 


0.2098 


0.2150 




0.250 


0.1350 


0927 


0.0875 


0.1573 


0.1625 




0.200 


0.1100 


0.0741 


0.0689 


0.1259 


0.1311 




0.1667 


0.0933 


0.0618 


0.0566 


0.1049 


0.1101 




0.1428 


00814 


0.0530 


0.0478 


0.0699 


0951 




0.125 


0.0725 


0.0463 


0.0411 


00787 


0.0839 




o.iin 


0.06S5 


0.0413 


0.0961 


00699 


0.t)751 


10 


0.10 


0.0600 


0.0371 


0.0319 


0.0629 


0.068) 



BOLTS AND NUTS 

T»bl« T. BkllMm StandkTd Square Thnkds 



J1 


"S-S 


la 


1^ 


% 


iiL 




1^ 


ill 


•3.a 


11 


Bt 


1 


1 

h 


i 

:*is7 


,1: 


4!i 

1' 


i 
i 


S7S 

1 


1 
i 


P 


1.20U 

i 


1! 




i 

1 













T>bU 8. V. 8. StutdATd Bolti uid NuU 



Rouihd. 






Tmbbed dimen 


■ioiu ol 


heodiudDUU 


Bud* Ud DUU 




H,„., 


1 held* and i>uu| ; 


Width 






Thiok- 
™ 


Width 


Width 




i 


8>K 

as 

UHd. 


■t^ 


1 


• 




In. 


T- 


in. 


ia 
nut. 






y 


















'K4 


;i- 






sss 




'■ 


[■ 








;s: 






'«J 
























!• 


"ill 


1 


1 


i: 


!f! 


1 




































i;«; 




























































































^ 


■■!i, 


2M. 


S'' 


wi. 


: J; 


IS 


^' 






162 



SCREW THREADS, BOLTS AND NUTS 



Table 9, Weight of 100 Bolti and Nuts, Lbs. 

(For Bolt Material Si>ecification8 Ree p. 127) 



Length under 
head, inches 


Bolts with square heads and nuts 


Bolts with hexagon heads and 
nuts 


Diameter of bolt, inches 


Diameter of bolt, inches 




W 


M6 


H 


Mo 


H 


H 


?4 


Ji 


1 


W 


H 


H 


H 


1 


1 






II 
II 
12 
13 
14 


15 
16 
17 
18 
19 


22 
23 
24 
26 
27 


37 
39 
41 
43 
45 


56 
59 
62 
64 
67 


84 
88 
93 
97 
101 


122 
128 
139 
139 
144 


19 
20 
22 
23 
24 


33 
34 
36 
38 
40 


52 
54 
57 
60 
63 


76 
80 
85 
89 
93 


no 

116 
12] 
127 
132 


Lb. per inch 
adaitional 


1.4 


2.2 


3.1 


4.3 


5.6 


8.7 


12.5 17.0 


22.3 


5.6 


8.7 


12.5 


17.0 


22.3 





Table 11. 


Safe Loads for XT. 8. Standard Bolts 




a 


No. of threads per 
in. 


Ultimate strength, lbs. per sq. in. 


a 


20,000 


40,000 


50,000 


60.000 


65.000 


80.000 


05.000 


8 

"3 


Alloy 


If 


Wrought 
iron and 
best rolled 
bronse 


Class B 
bolt mate- 
rial 


Class A 
bolt mate- 
rial 


Class A 
Nos. 1 and 
2 machin- 
ery forg- 
ings 


^h 


\ 


Cu, 88% 
8n, 10% 
Zn, 2% 


•all 


H 


20 


57 


115 


143 


172 


186 


229 


272 


ii* 


18 


99 


198 


247 


297 


322 


396 


470 


i 


16 1 


150 


301 


376 


451 


488 


601 


714 


H« 


14 


207 


415 


519 


623 


675 


830 


966 


H 


13 


282 


564 


704 


845 


• 915 


1.125 


1.340 




12 


365 


730 


912 


1,095 


1.186 


1,460 


1.730 


M 


II 


456 


913 


1.140 


1,370 


1.480 


1.820 


2,170 


U 


10 


690 


1.380 


'•^25 


2,070 


2.240 


2,760 


3.280 


H 


9 


964 


1.930 


2.410 


2^900 


3,140 


3,860 


4.580 




8 


1.265 


2.530 


3,170 


'•§59 


4.120 


5.060 


J:iJS 


IH 


7 


1,595 


3,190 


3,990 


4.790 


5,180 


6.380 


m 


7 


2.070 


^'^iS 


?'^*5 


6,210 


S'P2 


8.280 


9.830 


\H 


6 


2.440 


4,890 


6,110 


7,330 


7.940 


9,780 


11,600 




6 


3,020 


6,040 


7.540 


9,060 


9.800 


12,050 


14.300 


5V4 


3,530 


7.060 


8.820 


10.600 


11,500 


14.100 


16.750 


IH 


5 


4,060 


8,120 


10.150 


12.200 


13,200 


16.200 


19.250 


IH 


5 


4,800 


9.600 


12.000 


14.400 


15.600 


19,200 


22.800 


2 


4H 


5,360 


10.750 


13.400 


^*'!8? 


17,400 


21.500 


25.500 


24 


4H 


7.120 


14,200 


17,800 


21,400 


23.100 


28.500 


'?•% 


2H 


4 


8,750 


17.500 


21.900 


26,300 


28.400 


^5.?}? 


41.500 


4 


11.000 


22,000 


27.500 


33,000 


35,700 


44.000 


52,200 


3 


4 


13.400 


26.800 


33,500 


40.200 


43.600 


53.600 


63,600 


3M 


4 


16.100 


32,200 


40,200 


48.400 


52.JS2 


64.400 


76.400 


3H 4 1 


19.000 


38.100 


47.600 


57.200 


61.900 - 


76.200 


90.400 




4 


22.200 


44.500 


55.600 


66.700 


72.300 


89.000 


105.500 


4 




25,700 


51,400 


64,200 


77.000 


83.400 


102.800 


122.000 


4H 




29.350 


58,700 


73.400 


88.100 


'5'iK 


117,400 


139.300 


4H 




33,300 


66,600 


83.200 


100.000 


108.000 


133.000 


158.000 


4N 




37.400 


75,000 


93.700 


112.000 


122,000 


150,000 


178.000 


5 




41.900 


83.800 


105.000 


126.000 


136.000 


167.500 


199.000 


5H 




46,600 


93.200 


116.500 


140.000 


151,000 


186.000 


221.000 


5H 4 


51.500 


103.000 


129.000 


154.500 


167.000 


206.000 


2^'S9 


iH 


4 


56.700 


113.500 


142.000 


170,000 


184.000 


227.000 


269.000 


6 


4 


62.000 


124,000 


155.000 


186.000 


202.000 


248.000 


295,000 



OXY-ACETYLENE WELDING 

BY 

STUART PLUMLEY 

The Ozy-aoetylehe Process as applied to the welding of most metals and 
the cutting of iron and steel has become universal in recent years in connec- 
tion with almost every industry in which metals are used* 

OaiM. For welding purpoMS, oxygen and itcetylene are almost ex- 
clusively used. For brftsing, lead burning* etc., oxygen and hydrogen or 
oxygen and illuminating gas or natural gas are used to a large extent. For 
cutting, oxygen and acetylene are used to a greater extent than any other 
combination of gases, although for extremely heavy cutting, oxygen and 
hydrogen have been found advantageous. For all general cutting, the oxy- 
acetylene torch is preferable on account of its economy in consumption of 
oxygen and the rapidity with which the cut may be started. 

Oxygen is produced to an enormous extent in the United States by two principal 
procenes: (1) the liquefaction of air and the subsequent separation of the oxygen from 
the nitrogen and (2) the electrolysis of water. In the liquid air process the atmospheric 
sir is rednoed to liquefaction through pressure, refrigeration and expansion; in the liquid 
state and under pressure of a few pounds nitrogen, which liquefies at a lower tempera- 
ture than that of oxygen, will evaporate first, and pass out of the machine. The oxy- 
gen is collected in gas form in gasometers, and is afterwards compressed in oxygen 
cyhnders to a pressure of approximately 1,800 lbs. per sq. in. These cylinders are in 
daily use throughout the United States and may be obtained already charged from 
central distributing points located in almost every city. In the electrolysis process 
electric current is utilised in an electrolytic cell to break up water into its component 
parts, oxygen and hydrogen. 

Acetylene is usually generated in an acetylene generator. This generator contains 
calcium carbide in a hopper at the top of the machine and automatically feeds it into the 
water in the lower part of the apparatus. The reaction between the carbide and the 
water produces acetylene gas, which is piped directly to the point where it is used in the 
welding shop. Acetylene may thus be produced locally in any quantity required, and 
at a low operating cost. 

Acetylene may also be procured, compressed and dissolved in cylinders. These cyl- 
inders are charged at central producing points and shipped to the user as required. 
The cylinder is a special cylinder completely filled with a porous filler of cement, char- 
coal, infusorial earth, etc., the filler being saturated with acetone. Acetone has the 
property of dissolving acetylene and thus making it safe while under pressure. Acety- 
lene tanks are especially useful when the welding or cutting to be done necessitates the 
Qse d portable apparatus. 

Pressure regulators or pressure reducers are used to reduce the high 
pressure of oxygen in the cylinders to suitable lower pressures at the torch, 
and the much lower pressures of acetylene flowing from the acetylene cylinders 
(or from the acetylene generator, if in use). Pressure gages indicate the 
pressures in the cylinders and at the torch. Regulators should always receive 
careful treatment. They are a sensitive diaphragm mechanism, and the 
service is severe. If properly used they. will accurately regulate the gas 
pressure. 

163 



164 



OXY-ACBTTLBNE WXLDINQ 



The Ov-»Get7ltiM Bumer, known m the "torch," is connected to the 
BDUTce of supply by two lengths of hose. , It is simple in cooBtructioa. Fig. 
I shows how the oxygen and sjwtylene are brought together and intimately 
mixed in an interchangeable tip. This tip varies with the thiokness of weld 
and idle of flame required. It is essential that the two gases be brought 
together under indepeodeDt pressures, and that at the point of mixture the 
gas jets be directed together so as to produce the most thorough intermingling. 




^t.T^a'fyriv wh^h Carb^Ung Dt^ art Proportions 

VOfumfs of Otnforftnh Size of 
Flamt ProdiKHl 



L,mim-sCaniofFI(Mm 
Onef^jH- of Qtijgfn arxiOnt 
POrfofAcrhjttnt birn ond 
Wild Hj/drogtn and Corhcn 



'lamt,SO Easanftaf fo Oood YfgldirayWi 
linitwrn Consump/iBn ofOiij^in and 



Fio. 1.— Welding Toreh (See Table 1.) 
Table 1. Weldljv Torches 

{DatU-BoaniBntitU Co. StvU "C") 
ci-tylene and Oxygtn PrMura witb Styles M and II 



Tip 


Thi.^kirM 


Acclykne 


Oxygen 




o( m*t»l 


pKHure 




1 


'^M 


il 


'^'ih 


2 


M»^i.m 


2ih;- 


4I>». 


i 


HrH in 

si":!: 


31bs. 


tlbf. 


t 


4n». 

. ilbe. 


SIbs. 


i 


1i*-H in 


tiba. 


12 lbs. 


7 


It-S in 




Mlbe. 


S 


H -; in 


', 6\be. 


r6lb>. 




H-H In 


61b.. 




10 


M- Up 


1 6lb>. 


lOlb.: 




1 Extra 


»(bt. 


22]b>. 


12 


(Heavy 


an». 


»1bi>. 



... »...„u^..i«, operaton frequently adjust rnmlalor to 2 Iba. aboT« tliat ahovn In 
tmolt lot the siK of tip being used, which will aOow lor adiuatlni lor drop eausKi by 
lowering of pr«iure in tank, TaliatioOB in lacea, or other local causn. 



EXPANSION AND CONTRACTION 166 

Cb«raet6r of FUmi0. As shown in Fig. 1, the combustion of oxygen and 
acetylene produces a luminoas cone of flame at the tip of the torch which 
has a temperature of approximately 6,300 deg. F. This cone of flame is 
large or small, dei>ending upon the sise of the tip in use. If a heavy section 
of metal is to be welded, a large tip with a correspondingly large cone is 
reqaired. In iheet^ metal welding the tips are small and the cone of flame 
approaches the sise of a pencil point. 

For iron and iteel, oait Iron, east iteel, etc., a neutral flame is required. 
The neutrality of the flame is a very essential feature in connection with the 
welding of these metals. By a slight change in the adjustment of the needle 
ralves of the torch the flame may become neutral, oxidising or carbonising. 
The carbonising flame has an excess of acetylene, and the oxidising flame has 
an excess of oxygen. The flame is neutral when there is just enough oxygen 
and acetylene to produce combustion. If the welder does not use proper 
care in keeping the flame neutral he cannot expect to produce a good weld. 
Poor welding is often the result of carelessness in this respect. 

Oxy-aeetylene Welding consists of bringing the temperature of the two 
parts to be welded to the point of fusion by means of the torch flame. When 
in its molten condition, new metal is added to the fused mass by melting in it 
special welding stocks or rods made up of a suitable material for the work in 
process. When the two pieces to be joined have been fused or melted together 
in a mass without materially changing the characteristics of the metal, a 
weld has been accomplished. 

It will be appreciated, however, that in certain metals such fusion, or in 
fact the application of any degree of heat above the critical temperature, will 
utterly change the characteristics of the metal, and a weld in such instances 
cannot be made by the simple fusion of the pieces. This is true of malleable 
iron which, while it may not be welded as above described without re-anneal- 
ing, may be satisfactorily brazed with brass as a joining material under 
proper conditions. 

Bzpamaion and Contraetlon. All metals expand with heat and con- 
tract with cold. The amount of expansion caused in a steel plate by a con- 
■iderable rise in temperature is relatively small, but it acts with great force. 
In making a weld between any two pieces of metal conBideration nrust 
be giren to the effect of expansion and contraction. This is particularly 
true when dealing with a easting, especially one having restricted or confined 
members. 

Pre-heatlng. The stresses pM*oduced by expansion and contraction in the 
welded pieces may be so great as to break the weld or crack it when cold. To 
avoid such stresses the casting should always be pre-heated slowly and evenly 
by means of a flame which has a lower temperature and is not so concentrated 
as that produced by the oxy-acetylene torch. 

The most suitable apparatus for pre- beating is a fuel oil or kerosene 
homer, wfaieb produces a large, long, soft flame. The casting to be heated 
is set upon a layer of brick upon the floor of the shop, if the floor is of concrete, 
and in a convenient position for the welder. A rough fire-brick wall is then 
built up around it. The brick wall is covered over with a piece of sheet iron 
to retain the heat. The casting is thus heated evenly all over and each mem- 
ber » expanded. After the welding has been accomplished the easting is 
re>heated to take care of any stresses which may have been set up, and then 
allowed to cool very slowly by being covered with asbestos, hot sand, lime or 
ashes, to exclude the air. Such treatment will reduce stresses in the adjacent 
metal which might etherise have been set up. 



ie6 OXY'ACETYLBNE WBLDING 

If the fuel oil pre-heaters are not obtainable eharooal may be used, pref- 
erably with a little comprosaed air. If neither of theae can be obtained 
the casting may be set up on the fire brick so that the air will reach the char- 
coal fire. If the casting is extremely large it may be preferable not to heat 
it in its entirety, but any portion of it may be heated by btulding up that 
portion as described above. Large castings, however, require considerable 
skill in this respect so that preheating may be applied to the right members. 

Siae of Flame is governed by the amount of gas passing through the ports, 
and this flow of gas is controlled by the sise of the interchangeable tip. The 
tip should be chosen for the thickness of metal. Sheet metal will require a 
small flame and a small tip, while heavy plates require larger flames and larger 
tips. The sise of the flame must, in short, bear a certain relation to the sise 
of the work in order to obtain best results. Larger plates absorb and^dissipate 
the heat rapidly, and if insufficient gas is burned to raise the joint to the fusing 
temperature welding cannot be accomplished. Absorption of heat is reduceii 
by preheating, and rapid didaipation of heat is prevented by protecting the 
parts with some heat insulator like sheet asbestos, fire brick, etc. 

Preparing the Joint. If the parts to be welded are thin, little or no 
special preparation of the joint may be required, but on heavy parts it is 
necessary to chip away the edges to an angle of not less than 90 deg. This 
is necessary in order that fusion of the joint may begin at its lower surface. 
When the torch is applied to the bottom of the V the lower edges are fused, 
and the sides of the parts are slowly raised to a fusing temperature. 

When fusion has been accomplished throughout the immediate part of the 
section being welded, adding material is supplied by means of a suitable 
welding rod. It will, however, be appreciated that unless the joint is chipped 
away to permit the welder to begin at the bottom of the part, he cannot expect 
to create fusion clear through the section. 

Addinir Material (Welding Bods). Adding material is usually made 
up in the form of wire of various diameters and approximately in 36-in. 
lengths, or in cast form of various diameters and approximately in 20-in. 
lengths. These rods, which are generally called welding rods, must be of a 
suitable alloy for the work in hand. 

Most manufacturers, through a long series of experiments, have developed 
that certain alloys combined with certain fluxes produce the best results 
under given conditions, and it is essential that the welder keep this in mind 
in selecting a suitable welding rod for the job to be accomplished. 

While these rods are usually made up upon a special analysis or formula 
proven best by experimental work, it is also necessary that the rods be made 
up by a special method and under definite conditions in order to produce 
satisfactory results. Two rods of like analysis will not always produce the 
same result when used for welding, unless the method of manufacture has 
been the same. 

Manipulation of Torch see ^ig. 2. Select a suitable sise of tip for 
the work to be accomplished. This is generally shown in the manufacturer's 
pamphlets. Connect the torch to the source of supply of oxygen and acety> 
lene, also as described in the manufacturer's directions. Open the valvee, 
adjust the pressures and light the torch as indicated for the particular torch 
in use. 

It will be noted that when the pressure of each gas is properly adjusted 
the flame will possess a clearly defined luminous cone. If a little more acety- 
lene is turned into the torch a greenish tinge of flame will appear at the tap 



FLUXB3 



167 



of the luminous cone. If a little more oxygen is turned on the cone will 
beeome shorter and more transparent and less luminous. To be neutral 
the flame should be just between these points. There should be no greenish 
tinge, but the flame should be clearly defined and luminous. (See Fig. 1 for 
outline appearance of flame.) 

The work having already been prepared or preheated as has been described 
heretofore, hold tne torch in the right hand and the adding material in the left. 
Play the flame slowly along the edges to be united, beginning alwayv at the 
edges farthest away from the operator. Play the torch momentarily at this 
point and quickly fuse the sides of the V until a puddle is formed. Ap^ly 
the adding material in actual contact Tvlth the puddle and oscillate the torch 




Blench 




Remiraiion 'Fusion 
Sti^hfl^ Cromwd Weld 




Sccfkmal View. 



V 



H5* 



0- ^/f^pei 
Length 



H-. 



Fia. 2.— Manipulating the Torch. 
(Courtesy DaviB-Bournonville Welding Iiuititute.) 

slowly backward and forward in a semi-circle, keeping the flame and the 
tip pointing to the completed work. Oscillate the welding rod in similar 
manner to the torch, but in the opposite direction, which will keep the puddle 
free from inclusions of gas. Continue this motion and keep the puddle 
flowing constantly until the weld is complete or until the operator has reached 
the point where he can permit the work to cool down. Do not permit the 
hoi molten puddle to flow over the cold unmolten surface. If this is done, 
fusion between the puddle and the cooler surface will not occur, and a lap 
will be produced. Apply the torch in such manner that the parts being 
welded are always in a state of fusion before melting the welding rod into the 
puddle. 

FliiZM. The «fle«i of a flux is to lessen oxidation and reduce the oxide 
film that prevents perfect union. The choice of flux is important, as success 
may hinge on the flux used. Home-made fluxes generally lack the careful 
proportioning of ingredients and the thorough grinding and mixing necessaxy 
for best results. 



168 OXY-ACETYLSNB WELDING 

Direction of Weldinc- When, welding thin steel it ia customary to tack 
at the left and weld from the right. But when thick sections are welded the 
welding should proceed from the left, as shown in Fig. 2. The advancing 
puddle and side walls are thus kept directly under the flame, and lapping 
and cold shuts are more easily avoided. 

Welding 

Welding Cast Iron. Cast iron should always be preheated as described 
on p. 165. The edges of the crack or break should be carefully prepared before 
welding, by chipping away the metal so that there will be ample room to 
permit the welder to start fusion at the bottom of the groove. The casting 
should be placed in position so that its parts are in proper alignment and will 
remain so during welding. It is preferaHe to have the crack or break to be 
welded on the upper side of the easting. 

When this has been accomplished the casting may be bricked up, using a 
rough firebrick wall, and preheated as above described. When the casting 
has reached a temperature a little less than 4^11 red, the brick or cover may be 
removed to permit the welder to work. 

In welding cast iron a special cast-iron welding rod should always be used 
together with a proper flux. It is essential that the welding rod be high in 
eilicon and of good grade of cast iron, and the flux properly prepared to 
keep the metal flowing smoothly. 

As the sides of the V-break are fused and the added material united with 
the molten mass the welder uses the rod to scrape away any dirt or slag that 
may be encountered and to break up inclusions of gas*. When the weld is 
completed in this manner the casting should be covered up and the pre- 
heating burners re-lighted for a short period of time to bring the heat again 
sufficiently high to eliminate any strain or stresses which may have been set 
up. The casting should then be completely covered up and allowed to cool 
very slowly. 

Welding Malleable Iron. Welding malleable iron it not advisable 
except where high strength of the joint is not required. The effect of the 
process by which white cast iron is converted into so-called malleable iron is 
destroyed by fusing the metal, as it is changed again to brittle cast iron. 
Broken malleable parts may be strongly united by brazing with bronse weld- 
ing rods and flux. Care should be observed that too high a heat is not used 
in brazing. A full red heat produced by a neutral flame will yield best results. 
The iron and bronze should freely alloy in order to give a strong joint. 

Welding Steel. In welding steel, the welding rod used consists in most 
instances of a good grade of domestic iron wire, liquor drawn and annealed. 
In some instances it is preferable to use a low-carbon steel as a welding rod, 
but this depends upon the immediate case and the local conditions. 

The plates should be prepared by chipping the edges to an angle of 90 deg., 
and fusion should be produced at the bottom of the V and along its sides, 
before any welding wire is added. If the welder is not careful in this respect 
a series of cold-shuts and laps will be produced. Care must be taken not to 
burn the welding rod, and the puddle produced must be continually main- 
tained as far as is practicable. The speed of rotation of the flame as it is 
manipulated by the welder, and its advanoe aUmg tbe seam, mast be suited to 
the work in hand. 

Welding Steel Castings. Steel castings vary widely in carbon content, 
and no fixed rule can be given for welding. When the carbon content is 



WBLDINO VARIOUS METALS 169 

below twenty points (0.20), welding can be aooomplished with ease, but cast- 
ings with higher percentage of carbon are likely to give trouble. A little 
copper added to the weld will assist in difficult oaaes, but its use in general 
is to be avoided, aa it hardens the weld. 

Waldinff Cast Aluminum. The aluminum parts to be welded should be 
thoroughly cleaned to remove all grease, oxide and foreign material. The 
edges should be beveled the same as east iron and steel if the thickness exceeds 
M inch. Proheating ii highly important in the case of aluminum, on 
account of its rapid heat absorption and dissipation. To secure perfect 
welds it is necessary to preheat comparatively small parts all over to a tern- 
peratxue of about 600 deg. F. Adding material is supplied in alloy sticks 
which should be free from sand or other foreign matter. A flattened iron 
rod is required to puddle the melted aluminum, break up the oxide and make 
it fill the joint. Care should be taken not to heat the end of the rod to a 
high temperature, as the resulting iron oxide will mix with the melted alumi- 
num and cause a defective weld. 

Welding Shoet Aluminum. Sheet aluminum is welded with aluminum 
flux and drawn aluminum wire adding material. Care must be taken to 
choose a sise of tip suited to the work. The operator must work rapidly, as 
thin sheets heat to. the fusing point quickly, and the welding must be accom- 
plished without delay in order to obtain a smooth, clean job. 

Welding Copper. Copper welding requires a larger tip and flame than 
steel of the same gage, because of the greater heat radiation, and the preheat- 
ing of comparatively large pieces is necessary. It is desirable to use a flux 
and a strictly neutral flame to prevent oxidation and consequent weakening 
of the joint. The joint has the tensile strength of cast copper, but it may 
be increased by judicious hammering. 

Welding JBrais and Bronie. Care should be exercised in welding brass 
and bronse, not to overheat the metal and volatilize the zinc or tin. The 
white fumes resulting from overheating with the torch are poisonous, and the 
operator should avoid breathing them. A flux should be used, and preheating 
will be neeessary on large pieces. Use special cast-bronse welding rod for 
adding material. 

Welding Catt Iron and Steel. The steel must first be heated to the 
welding temperature, as its fusing point is higher than that of cast iron. The 
torch flame is then directed against the cast iron, and, as fusion begins, adding 
material is supplied from regular cast-iron welding rods or sticks. The parts 
to be welded should be prepared the same as described for other metals. A 
cast-iron welding flux will facilitate the work, and is recommended. 

Welding Copper and Steel. Heat the steel to the welding point and 
Apply the copper, letting it absorb heat from the steel until it begins to melt. 
The flame shoiild be withdrawn as soon as fusion starts. 

Weldinf Hiirh-8peed Steel and Machine Steel. High-speed steel 
may be used economically for lathe and planer tools by welding cutting bits 
to machine steel shanks. The high-speed steel piece should be fitted to a 
notch in the end of the shank, which will afford support beneath. The sides 
of the bit to be welded should be heavily coated or "tinned" with soft iron 
welding rod, and when this is accomplished the welding to the shank is done 
in the usual way. The welding of high-speed drills to machine-steel shanks 
by the oxy-acetylene process can be done successfully, but is not advised 
unless speeial facilities are provided. If necessary for special work to provide 



170 



OXY'ACETYLBNB WELDING 



a few ioDg-shank high-epeed drills, scarf the shanka and driUa, and unite by 
brasing, using bronse welding rod and flux. 

Weldinir Dissimilar Mstals in General. Metals haying widely diilerent 
melting temperatures may be successfully united by coating or "tinning" 
the metal having the higher melting point, with the metal having the lower 
melting point. Then the two are fused together. The flux to be used de- 
pends on the metals to be welded. 



.. Conkcri Ground Staf. 



Pnhtafing Ace'h/ftm, 



ir*r 



 ••«4«a^»»«»«Maa«tii««V»tMI< 




rhngOxygtn 
''Actfylm*. 
^""Copper Tip. 
•Pnhtafing Fknm., Oxifftn 

CtrH-ingJif CuHiry K»/>». 





Onfftn CMnqJwf 
Iriggwr Valvrlf will 
Rtmam meifhtran 
Optn orChMcl Ihsrhon. 



•RmTKMxbh Plug. 



Ci/Hm^ Va/yw Trmwt^ 'Pbckinef "^'Spring 
Remams m Opvi f^jSrion. ^^• 

Derails of OxiMin Cuffing Valv« Wiihin 
Hcrndie of Torch. 

Fio. 3. — CuUing Torch. 






Tables. Cutting Torches 

{Davu-BournonviUe Co. Style "C") 
(Approzimstc Acetylene and Oxygen Pressures with Style 12 Tips) 



Tip 
No. 


Thickness 
of metal 


Acetylene 
pressure 


Oxygen 
pressure 


1 
1 
1 

1 


H in. 
Me in. 
H in. 
Me in. 


3 lbs. 
3 lbs. 
3 lbs. 
ilbs. 


10 lbs. 
15 lbs. 
20 lbs. 
20 lbs. 


^ 


H in. 

H in. 

H in. 

in. 


3 lbs. 
3 lbs. 
3 lbs. 
3 lbs. 


10 lbs. 
20 lbs. 
30 lbs. 
35 lbs. 




1 in. 
1V6in. 

2 in. 

3 in. 


41bs. 
4Ibs. 
4 lbs. 
4 lbs. 


30 lbs. 
40 lbs. 
SO lbs. 
60 lbs. 




3 in. 

4 in. 

5 in. 

6 in. 


5 lbs. 
SIbs. 
5 lbs. 
5 lbs. 


60 lbs. 

70 lbs. 

85 lbs. 

100 lbs. 




6 in. 

7 in. 

8 in. 
10 in. 


6 lbs. 
6 lbs. 
6 lbs. 
8 lbs. 


90 lbs. 
100 lbs. 
125 lbs. 
ISO lbs. 



OXY'ACETYLSNE CUTTING 171 

Cutting 

OuMng Iron and 8tMl. A gpeoUl type of oxy-aoetylene torch is 
made for cutting wrought iron and steel. The action of cutting iron and steel 
is based on tha principle that wrought iron and steel will be oxidised or burned 
wlien raiaed to a red heat and eziKieed to a iet of oxygen gas. 

The appatetiu for cutting differs in the type of torch and the oxygen 
working preasure, the pressure being much higher for cutting than for welding. 
The construction of a cutting torch is shown in Fig. 3. 

Mftchinos for Cutttng. A number of ingenious machines have been 
developed for holding and guiding the cutting torch. They make it possible 
to out die bliwiks and all sorts of forms accurately from thick plates. 

Speed of Cutting. The speed of cutting depends upon the sise of the 
torch, gas oonsumption, and thickness of steel. It is not unusual to cut 
H'iu. steel at the rate of 15 in. per min. 

Depth off Gutting. The depth or thickness that can be cut b remarkable. 
Armor plate up to 16 to 18 in. thick can be cut quicker and cheaper than by 
toy other method. Cutting to depths of 6 to 8 in. is well within the skill of 
ordinary operators. With mechanically operated torches thicknesses up to 24 
m. may be readily cut. 



THE THERMIT WELDmG PROCESS 

BY 

JOHN H. DEPPELER 

Reference: R. L. Browne, paper presented before N. Y. R, R. Club, April 
19, 1918. 

This process was first introduced commercially in 1902 and is fundamen- 
tally adapted to the welding of heavy cast iron and Bteel sections. Sec- 
tions under 1 in. in thickness and sHeet steel do not readily lend themselves 
to the Thermit process, therefore this process' does not conflict with oxy-acety- 
lene, electric or other autogenous welding processes which are specially 
adapted to welding such parts. In marine repairs, the field of application 
of the Thermit Process embraces the welding of broken stern frames, rudder 
frames, crank shafts, tail shafts, anchors, davits and similar heavy sections of 
vrrought iron and steel. 

This process is specially valuable for large marine repairs owing to the fact that dry 
dockage is extremely coetly. Such repairs as stern poet welds are usually executed by 
contract and seldom keep the vessel in dry dock more than 48 hours. The U. S. Navy 
was one of the first to appreciate the advantage of the process and has used it extensively 
at its various yards. A number of Navy repair ships are completely equipped with 
Thermit welding outfits. 

Composition. Thermit is a mixture of finely divided aluminum and 
Iron ozlde in such proportions that upon reaction the Al combines with all 
the O of the iron oxide according to the formula 2A1 -|- FesOs « 2Fe + 
AI2OS. An approximate temperature of at least 2200 deg. F. Is required to 
start the reaction. This temperature is obtained by means of a special 
barium compound ignition ];>owder. 

The reaction, which is started in one Bx>ot, supplies its own heat and spreads gradually 
throughout the entire mass. The aluminum oxide (slag) floats on top of the iron which 
is precipitated to the bottom of the containing vessel in the form of a highly superheated 
low carbon liquid steel. The temperature of the reaction is not measureable by any 
pyrometer but has been calculated theoretically by Profe*»or Joseph W. Richard* of 
Lehigh University as 4881 deg. F. The reaction of quantities of Thermit ranging from 
a few pounds to 1000 lbs. is completed in from 25 to 50 sec. 

Thermit produces half Its weight in liquid steel but in practice the 
amount o.f steel is increased by mixing from 15 per cent to 25 per cent of 
small mild steel punchings with the Thermit mixture: less than 500 lbs. of 
Thermit about 15 per cent of punchings; from 600 to 1,000 lbs. of Tnermit, 
25 per cent of punchings. 

Kinds of Thermit. At the present time there are three varieties of 
Thermit produced for welding purposes: (1) Railroad Thermit; (2) Plain 
Thermit; (3) Cast Iron Thermit. 

Plain thermit is simply a mixture of aluminum and iron oxide and is used 
in making pipe welds where the Thermit is merely used as a heating agent to 
bring the pipe ends up to a welding temperature. 

Railroad thermit is Plain Thermit with the addition of ^ per oent 
nickel, 1 per cent manganese and 15 per cent mild steel punchings. This 
grade of Thermit is used in connection with all steel and wrought iron welds. 

172 



LARGE WELDS 



173 



CaAt iron thermit is Plain Thermit with an addition of 3 per oent ferro- 
silicon and 20 per cent mild steel punchings and is used for welding cast iron 
parts. 

Phyiicml propertieg of Railroad Thermit shown by recent tests made on a 
sample taken from one of the gates of a weld and forged are: Tensile strength 
72,000; elastic limit, 58,400; elongation in 2 in., 17.5 per cent; reduction in 
area, Q4 per oent. 

Larye wolds are made by casting Railroad Thermit steel around and 
between the parts to be welded together. The parts to be united are* first 
arranged with a space between them, the extent of which depends upon the 
sise of the sections to be welded, see table 1 ; a section 6 in. X in. would call for 
1^ in. opening. 



TABUB 1. Woldlnf Portions Por Welding Beotancrulftr Bootions 



Width of Sec- 
tion 


Depth of Sec- 
tion 


Width of Ther- 
mit Steel Collar 


Thickness of 

Thermit Steel 

Collar at Center 


Quantity of 
Thermit* Re- 
• quired for Weld 


Inches 


Inches 


Inches 


Inches 


Pounds 

1 




2 4 


1 


40 




2^i 




1 


40 








1 


45 




3H 




1 


50 








1 


55 








1 


65 




4^ 




1 


65 








1 


70 




5H 


^ 


^}^ 


75 








1^ 


75 


4H 


4H 




m 


70 


4W 


5 5 


m 


75 


4H 


5J4 


5 


IM 


75 


4H 




5 


m 


80 






5 


IM 


75 




5Vi 5 


IH 


80 








m 


85 








m 


90 


5H 


5H 




m 


85 


5H 






m 


90 


5H ^ 






U4 


110 








m 


100 




6H 




\H 


120 




7 7 


iH 


130 


6^ 


6H 1 7 


IH 


130 


6W 




7 


X m 


150 


6H 




7 ! IH 


• 160 




7 7 IH 


155 



"Railroad Thermit for Wrougtit Iron and Steel. 
Cast Iron Thermit for Cast Iron. 

Where the piece to be welded is in two parts it is a simple matter to provide this space 
but in the ease of a crack, it is necessary to cut out sufficient steel to provide this space. 

The objeet of this space b to properly preheat the ends to be welded and confine 
enoiich superheated Th^mit steel around and between these ends to thoroughly melt 
them up and amalgamate with them. 

After the space is provided, a wax pattern is formed around the ends to be 
united of the exact shape of the reinforcement of Thermit steel which is to be 
east at this point to make the weld. The object of this reinforcing collar is 
principally to proride sufficient heat to assure perfect fusion of the interior 
of the weld and the complete welding of the outer fibers. 



174 THE THERMIT WELDINO PROCESS 

A MUld mold U next rammed around the wmc pattern and iiuide a sheet 
iron box, providon being made in the mold at the lowest point of the wu 
pattern for a pourins gate and a heating gate and at the highest point for a 
rieer. The gatee and riser openings in the mold are made with the aid of 
woodan pattomB wliich are withdrawn after tbe mold is completed, Fig, 1. 

^vr/'rKt Bonn to 




a ffwms SRidng-^FiraSand,lifireaay.iGmundfirr8ne», 
 WiOrtKa ^Loam,»-miituraof%SharpStrtcl, I^FirtClof. 
BJ>iv) PIi^ crSand Flour Con. 

Ro, 1.— Mold Conetruetion, Thermit Welding. 




AA-Ma«De«ia Sione. 
BB— Mscneaia Thimble 

C— Rsfraotory Sand. 

O-Matal DJio. 

E— Aebeetoi Wuher. 

Tia. 2. — Crucible Section, Showing Flag. 

Tbe function of the vent holes !■ primarily to vent the interior of the mold 
and prevent the occlusion of gases. The baain shown on tbe lop of the mold 
is for the purpose of CBtching tbe slag. 

Tbe flame of a oompresaed air gasoline or keroaene heater directed into the 
heating gat« melta the was patteni and leaves a space (later occupied by the 



CRANK SHAFT RSPA1R8 



176 



Thermit steel) between and around the ends to be welded. After the wax 
is melted out heat is continued un Ji the parts to be welded have been brought 
to a red heat and the mold is thoroughly dried out. 

The charge of Thermit is placed in a conicid thftpe sheet fteel erudble 
lined with magnesite and supported over the prouring gate of the mold 
When the sections to be welded are red hot and the heat has been allowed to 
soak in so that the pieces will retain this beat, the burner is removed, the 
heating gate plugged up, and the Thermit charge in the crucible ignited. 
When the reaction is completed the Thermit steel is tapped from the bot- 
tom of the crucible into the mold in bulk where it flows around and between 
the sections to be welded together uniting them into one solid mass forming 
a cast weld. Fig. 2 shows the cross section of the crucible plugged, ready to 
receive the Thermit. 

The mold is allowed to stay in place sufficiently long to insure slow cooling* 
When the mold is stripped, excess metal in the pouring gate and riser is 
removed and, if necessary, the Thermit steel collar surrounding the weld can 
also be removed. (If not necessary, it is left on to add strength to the repair). 
The adyants^TM of the process for large welding operations are: 

(1) Portability of outfit enabling welds to be made anywhere that compressed air is 
available; (2) welds made without removing broken section from their poeitions; (8) 
steel to make the weld is produced in bulk and poured around the sections in one opera- 
tion so that internal shrinkage strains are eliminated. The only shrinkage to allow for 
is shrinkage tending to draw the two parts together and allowance for this can be easily 
and accurately made; (4) results aie not dependent on the skill of the operator, as in the 
case of other welding processes. 




THERMIT PIPE WELDING OPERATION 

1— Slaf flowing into mold and coating outaidc of pipe and 

inside of nwld 

2 — Stag in mold and steel following, difpUcing alag in bot- 
tom part 

.3— Jloth »laj and steel in mold but steel separated from pipe 



Fig. 3. 



Grmak. Shaft Bepairs. Heavy crank shaft repairs present a very interest- 
ing application of the Thermit Process. There is no limit to the siae or weight 
of shaft that can be welded but the shafts most frequently encountered vary 
from 6 in. diameter up to 14 in. diameter, and sometimes weigh as much as 
10 tons. In making a crank shaft weld the parts of the shaft are supported 
in the prop^ position by "V** blocks mounted on a machined bed plate. The 
fracture is cut out and a space provided in the usual manner. The parts of 
the shaft are separated a certain amount to allow for the contraction which 
will subsequently take place, and held rigidly in line by means of clamps 



176 THE THERMIT WELDING PROCESS 

during the operation of ramming the mold. After the mold is rammed, these 
clamps are removed so that both ends of the shaft will be free to move during 
solidification and contraction of the weld, thus avoiding all possibility of the 
setting up of shrinkage strains. In fact, the shaft can not only move length- 
wise in the *'y" blocks but the "Y" blocks are so arranged as not to restrict 
even side motion of the shaft. It is obviously impossible to guarantee perfect 
alignment of the welded shaft because it is most essential that no shrinkage 
strains be introduced, and slight inaccuracies in alignment are of lesser 
importance. It is furthermore a fact that the strain that caused the fracture 
of the shaft originally, undoubtedly was sufficient to distort the shaft at other 
points and thus necessitates machining subsequent to welding. It is always 
understood, therefore, in connection with crank shaft repairs that, after 
welding, a slight finishing cut will have to be taken from the weld to the 
shorter end of the shaft. This necessitates the relining of the bearings at 
this end to compensate for the slight reduction in shaft diameter. Usually 
it is not necessary to machine the pin journals as the inaccuracy is very slight. 
In the event of an end main journal being broken off, it is usually preferable to 
discard the piece and weld on a new billet slightly larger in diameter, thus 
necessitating no change In bearing sixes. 

Pipe Welds. Plain Thermit is used for butt welding pipe lengths to- 
gether. A cast iron mold is provided and the pipe ends are accurately faced 
and held tightly together by clamps. The Thermit is reacted in a flat bottom 
crucible similar to a small foundry ladle, but lined with magnesite, and on com- 
pletion of the reaction the contents are poured into the mold, Fig. 3. Slag 
first enters and coats the Inside of the mold and the outside of the pipes with 
a protective coating. This prevents the steel (which follows the slag) from 
touching either the mold or pipes. In this case the Thermit steel does not 
comprise the weld but acts merely as a heating agent, advantage being taken 
of the extremely high temperature of the chemical reaction to bring the pipe 
ends to a welding heat, at which time they are drawn together by means of the 
clamps and a butt weld obtained. These welds are largely used for ammonia 
refrigerating pipe. Two men can make from 40 to 60 medium size pipe 
welds per day. 

In iron and steel foundry practice, Thermit is used to increase the 
temperature of iron and steel. For this purpose it is put up in cans that may 
be introduced into the foundiy ladle. It is also used in casting risers to keep 
the metal liquid for a longer time than usual. This allows a better oppor- 
tunity for gases to escape, and thus improves the quality of caatingB. 



HEAT 

BT 

O. A. GOODENOUGH 

From the "Meobaxiical EncinMn Handbook" by courtMy of the Editor-in-Chief 
thereof, Lionel S. Marks. 

RBVKBBccai: Preeton, "Theory of Heat,'* Macmillan. Zeuner, "Technioal Thermo- 
4ynami«t.'* Van Nostiand. Goodenough, "Prinoiplea of Thermodynamics," Holt. 
Marks and Dayie, "Steam Tables and Diasrams." Longmans Green. Bryan, "Ther^ 
■lodynamies," Teubner.  Peabody. "Thermodynamics of the Steam Engine," Wiley. 
Lneke. ''Engineering Thermodynamios," MoGraw^Hill. Bulletins 80, 40, 66, 76, En- 
ijafuffing Eipcriment Station, UdIt. of Illinois. 

THERMAL PBOPIBTIE8 OF BODIES 
The Moafurement of Temperature 

ThermoineterB. The scale of the constant-volume hjdtogm ther- 
mometer 18 taken as the standard temperatiire scale. Within the limits of 
ordinaiy use the scale of the mercury thermometer agrees closely with the 
standard scale, but above 500 deg. fahr. the divergence between the two scales 
may be api>reoiable. 

The ordinary mercury thermometer may be used to about 600 deg. fahr. ; 
this limit may be extended to 1000 deg. fahr. if the capillary tube above the 
mereuiy is filled with nitrogen or carbon dioxide under high pressure. The 
lower temperature limit for the mercury thermometer is —39 deg. fahr. For 
lower temperatures, alcohol, pentane or petroleum ether may be used as the 
tbermometrio substance. Very high temperatures are measured by various 
forms of pyrometen. See pp. 316-318. 

Thermometer Scalea. Let F and C denote the readings on the Fahren- 
bsitand Centigrade (or Celsius) scales, respectively, for the same temperature; 
then 

C - HiF - 32), F - HC + 32 

Tiled Temperatures. The fixed temperatures in Table 1, adopted by 
the U. S. Bureau of Standards, are useful in the calibration of pyrometers* 

Tahle 1. Fixed Temperatures, U. S. Bureau of Standards 

Uqvid tin BoUdifies at 

Uqnid lead solidifies at 

Upad lino soUdifiea at 

liooid solphur boils at 

Uvnid antimony aohdifiee at 

liquid aluminuns (97.7 per cent pure) solidifies at 

ScBdgold melU at 

IMd eopper solidifies at 

Bdftd niekel melts at 

Mid paOadiam nkelts at 

Mid platlnam mehs at 

Blfh Temperatures and Color. High temperatures may be Judged 
anmnimately by color, though the estimate of an experienced observer 
IS fikely to be 100 deg, fahr. from the true value. The following table as- 
sociate eolov and temperature of iron or steel is due to White and Taylor. 

177 



Deg. fahr. 


Deg. cent. 


449 


282 


621 


827 


787 


419.4 


883.6 


444.7 


1167 


680.6 


1216 


668 


1947 


1064 


1983 


1084 


2616 


1435 


2816 


1546 


3187 


1763 



178 



HEAT 



Deg. fahr. 

Dark blood red, black red. . . 990 

Dark red, blood red, low red . 1050 

Dark cherry red 1 175 

Medium cherry red 1250 

Cherry, f uU red 1375 

Light cherry, light red 1550 



Deg. fahr. 

Orange, free scaling heat 1650 

Light orange 1725 

Yellow 1825 

Light yellow 1975 

White 2200 



Expansion of Bodies by Heat 

Coefficients of Ejq>ansion. The coefficient of linear expansion of 

a solid is defined as the increment of length in a unit of length for a rise in 
temperature of 1 deg. Likewise, the coefficient of cubical expansion 
of a solid, Uquid, or gaa is the increment of volume of a unit volume for a 



Table 2. Coefficients of Linear Expansion 

(For pure metals, see p. 41) 



Coefficients of Linear Expansion 
(Mean values of 10,000a' between 32 and 212 deg. fahr.) 



METALS 

Aluminum bronie 

Brass, oaat 

Brass, wire 

Bronse 

Constantan (60 Cu, 40 

Ni) 

German silver 

Iron: 

Cast 

Soft forged 

Wire 
Masn^um '(86* Al', 'iS 

Mg) 

Phosphor bronae 

Bolder 

Speculum metal 



0.094 
0.104 
0.107 
0.100 

0.095 
0.102 

0.059 
0.063 
0.080 

0.133 
0.094 
0.134 
0.107 



Steel: 
Bessemer, rolled hard. 0.056 
Bessemer, rolled soft. 0.063 
Nickel(10% Ni) 0.073 

Type metal 0. 108 

OTHEB MATEBXALS 

Brick 0.031 

Caoutchouc 0.372 

Carbon — coke 0.030 

Cement, neat O.060 

Concrete 0.080 

Ebonite 0.468 

Gloss: 

Thermometer 0.045 

Hard 0.033 

Plate and crown.. . . 0.050 
Granite 0.048 



Graphite 0.044 

Gutta percha 1 . 100 

Limestone. 0.014 

Marble 065 

Masonry 0.025 to 0.050 

Porcelain 0.017 

Rubber 0.428 

Vulcanite 0.400 

Wood (H to fiber): 

Ash 053 

Chestnut and maple 0.036 

Oak 0.027 

Pine 0.030 

Across the liber: 

Chestnut and pine. . 0.019 

Maple 0.027 

Oak 0.030 



Table 3. Coefficients of Cubical Expansion 

(Mean values* of 1000a"' at ordinary room temperatures) 



liquids 

Aeetio add 0.80 

Alcohol (ethyl) 0.61 

Alcohol (methyl) 0.80 

Benxene 0.77 

Bensol 0.70 

Calcium chloride 
(CaCls); 5 to 60% 

solution 0.28 

Chloroform 0.77 

Ether 1.20 

Glycerine 0. 28 



Hydrochloric acid 0.27 

Hydrochloric acid, 

50 % solution 0.52 

Mercury 0. 10 

OUveoil 0.41 

Petroleum 0.55 

Phenol (CeHeO) 0.50 

Rape-seed oil 0.50 

Sodium chloride: 

1.6% solution 0.60 

26% solution 0.24 

Sulphuric aoid 0.27 



Sulphuric acid. 60 % 

solution 

Turpentine 

Water 

SOLIDS 

Fluorspar 

Ice (4 to 30 deg. fahr.) 

Paraffin wax 

Rock salt 

Sulphur 

Wood (beech) 

Wood (pine) 



0.45 
0.56 
0.10 



0.035 
62 
61 
67 
40 
016 
02a 





0. 





0. 



EXPAI^SJOS OF BODIES BY HEAT 



179 



iiB0 of temperature of 1 deg. Deooting these coeffioiente by a' and a"\ 
mpeotively*. 

^ '^l di * "F A 

in which 2 denotes length, V volume, and t temperature. For homogeneous 
lolids o^" « 3o'. and the coeffleient-of superficial ezpaiurioii o''«-2a'. 
The ooeffieiente of expansion are in general dependent upon the temperature, 
bat for ordinary ranges of temperature constant mean values may be taken. 
If lengths, areas, and volumes at 32 deg. fahr. (0 deg. cent.) be taken as 
standard, then these magnitudes at other temperatures t\ and t% are related 
SB follows: 

h . ^ +«'<! :dl « 1 -i-g"fa Zj . 1 -\-a'"ti 

h * 1 +o7i At " 1 +a"<t V% " 1 +o'"f» 

 

Sinee for solids and liquids the ezpansioi) is small, the preceding formula 
for these bodies become approximately 

U -li - aMtt - h)- At" Ai^ a"Ai{t% - U). Vt - Vi « a'"Vi{it - tx) 
For certain metals the variation of the coefficient of expansion with 
temperature has been investigated by Holborn and Day and by Ditten- 
berger. Denoting by 2o the length at 32 deg. fahr., and by / the length at 
temperature t, the following relation is obtained. 



1000 
The following table gives values of the constants. 



Metal 



1000 a 



1000 6 



Temperature range, 
deg. fahr. 



Aluminum.. . . 

Out iron 

lacot iron 

MaUtoble iron. 
I^otateel 



m: 



13.380 
5.441 
6.375 
6.503 
6.212 
9.278 
7.652 



2.182 
1.747 
1.636 
1.622 
1.623 
1.244 
1.023 



32-1130 
32-1160 
32-1380 
32- 930 
32-1380 
32-1160 
32-1830 



The tensile or compressive Btrets set up in a prismatic bar by a tom- 
penture chaniTO of ^deg. is P => a'EAU in which E denotes the modulus of 
slsstioity and A the area of the cross-section. 

The linear ghrlnirage of castingt is approximately as follows: 



Bu iron, rolled. ... 1 : 55 

Bdmetal 1:65 

Bhmath 1:265 

Bhut 1:65 

Btonie 1:69 



Cast iron 1:96 

Gun metal 1 : 164 

Iron, fine grained. ... 1 :72 

Lead 1:02 

Bteel castings. ....... 1 : 50 



Steel, puddled 1 : 72 

Steel, wrought 1:64 

Tin 1:128 

Zino, oast It62 

8Cu + lSD(bywt.). 1:134 



IftO 



HEAT 



Table i. Volume. Denilty and Bpedflo Heat off Wator at Batura- 

tion FreMure 

(From M»rki and Davis's Steam Tables) 



Temp., 
deg. 
fahr. 


Pree- 

Bure, 

lb. per 

sq. in. 


Spedfift 
volume, 

cu. ft. 

per lb. 


Den- 

lb. "pm 
ou. ft. 


Speei- 
fio 
heat 


Temp., 
deg. 
fahr. 


Pies- 

Bure, 

lb. per 

Bq.m. 


Speeifie 
volume, 

eu. ft. 

per lb. 


Den- 

lb. per 
ou. ft. 


Speci- 
heat 


20 
30 
40 
50 
60 


0.06 
0.08 
0.12 
0.18 
0.26 


0.01603 
0.01602 
0.01602 
0.01602 
0.01603 


62.37 
62.42 
62.43 
62.42 
62.37 


1.0168 
1.0098 
1.0045 
1.0012 
0.9990 


240 
250 
260 
270 
280 


24.97 
29.82 
35.42 
41.85 
49.18 


0.01692 
0.01700 
0.01706 
0.01716 
0.01725 


59.11 
58.83 

58.55 

58.26 
57.96 


1.012 
1.015 
1.018 
1.021 
1.023 


10 

ao 
w 
too 

110 


0.36 
0.51 
0.70 
0.95 
1.27 


0.01605 
0.01607 
0.01610 
0.01613 
0.01616 


62.30 
62.22 
62.11 
62.00 
61.86 


0.9977 
0.9970 
0.9967 
0.9967 
0.9970 


290 
300 
310 
320 
330 


57.55 
67.00 
77.67 
89.63 
103.0 


0.01735 
0.01744 
0.01754 
0.01765 
0.01776 


57.65 
57.33 
57.00 
56.66 
56.30 


1.026 
1.029 
1.032 
1.035 
1.038 


120 
130 
140 
150 
160 


1.69 
2.22 
2.89 
3.71 
4.74 


0.01620 
0.01625 
0.01629 
0.01634 
0.01639 


61.71 
61.55 
61.38 
61.20 
61.00 


0.9974 
0.9979 
0.9906 
0.9994 
1.0002 


340 
350 
360 
370 
380 


118.0 
135.0 
153.0 
173.0 
196.0 


0.01788 
0.01800 
0.01812 
0.01825 
0.01839 


55.94 
55.57 
55.18 
54.78 
54.36 


1.041 
1.045 
1.048 
1.052 
1.056 


170 
180 
190 
200 

210 


5.99 

7.51 

9.34 

11.52 

14.13 


0.01645 
0.01651 
0.01657 
0.01663 
0.01670 


60.80 
60.58 
60.36 
60.12 
59.88 


l.OOIO 
1.0019 
1.0029 
1.0039 
I.OOSO 


390 
400 

410 
420 
430 


220.0 
247.0 
276.0 
308.0 
343.0 


0.01854 

0.0187 

00189 

0.0190 

0.0192 


53.94 
53.5 

53.0 
52.6 
52.2 


I.Ott 
1.064 
1.060 

ion 

1.077 


220 
230 


17.19 
20.77 


0.01677 
0.01684 


59.63 
59.37 


1.007 
1.009 


440 


381.0 


0.0194 


51.7 


1.082 



Bpedfle Heat 

Unit! of Boat. The mean Britiih thermal unit (B.t.u.) is defined as 
the Hto part of the heat required to raise the temperature of 1 lb. of water 
from 32 deg. to 212 deg. fahr. This is substantially equal to the heat re- 
quired to raise 1 lb. of water from 63 deg. to 64 deg. fahr. 

The mean ealorle is >loo of the heat required to raise the temperature of 1 g. of water 
from d^. to 100 deg. cent. It is practically the same as the 17^i-deg. calorie, that is 
the heat required to raise 1 g. of water from 17 deg. to 18 deg. cent. The 15-deg. calorie 
is also used extensively. Because of the Tariation of the heat oapaeity of water, this is 
slightly larger than the mean or 17H-deg. calorie. The present tendency is toward 
the mean calorie (and mean B.t.u.) as the standard heat unit. 

In countries wUch have adopted the metric system, engineers employ the kUogram 
ealorie {at "large calorie") as the unit in heat measurements. 1 kilogram calorie » 
1000 g. calories >■ 8.068 B.t.u. (1 B.t.u. - 0.262 kilogram calorie). This is the 'V&rme* 
einheit'* (WE) mentioned in German texts. 

Speeifle Heat. The specific heat of a substance ia the ratio of the heaf 
required to raise the temperature of unit weight of the substance 1 deg. to 
the heat required to raise the temperature of unit weight of water 1 deg. 
at Bome specified temperature. The specific heat is thus numerically equal 
to the quantity of heat required to raise the temperature of a unit weight of 
the substance by 1 deg. 

Denoting by c the specific heat, the heat required to raise the temperature 
of M lb. of a substance from (i to ft isQ «■ Mc{t% — fi)« provided c is a constant. 



SPECIFIC HSAT 



181 



In general, c varies with the temperature, though for moderate temperature 
T&nges a constant mean value may be taken. If, however, c is taken a» 

variable, then Q -■ ^ Jix ^- 1*^^ mAan specific heat from deg. to i deg. 

is given by c«, "■ r /* octt. If e — ai + oa^ + oa^* + . . . , 

tM^ ax->r yiadt + Hai<* + . . . 
Bpedilo Heat of Water. The specific heat of water between 32 deg. and 
212 deg. fahr. has been investigated by Barnes, Ludin, Dieterioi, and others 
(see Marks and Davis's "Steam Tables," p. 88). For this range of tem- 
peratures, two distinct values of the specific heat may be noted, according 
88 (1) the pressure on the water b the saturation pressure corresponding to the 
temperature, or (3) constant atmospheric pressure. In Table 4 the values 
of the specific heat are according to the first system. For « full discussion 
of this topic see Marks and Davis's "Staam Tables," p. 90. 



Table «. 



Moan Specific Heatg of Various Solids and Liquids 
Between 82 and %i2 Deg. Fahr. 



(For 



B«e p. 201; for pure metals, p. 41) 



eouDS 
AHan: 
Biimath-tin ... 0. 040-0. 045 

Bell metal.'. O.066 

BnsB, yellow O.0683 

Braaa, red 0.090 

Bronie 0.104 

Conetaotan 0.096 

D'Aroet'B metal. ... 0.050 

German silver 0.095 

Lipowits'a metal. .. 0.040 

Nwkel Steel O.I09 

Bose'a metal O.OSO 

Soldera (Pb and Sn) 

0.040-0.045 

Asbettot 0.20 

Aahes 0.20 

Borax 0.229 

Brick. 0.22 

GuboDHMke O.209 

Chalk 0.215 

Charcoal 0.20 

Ciiidera 0.18 

Coal 0.314 

Cork 0.485 



Corundum 0. 198 

Dolomite 0.222 

Ebonite 0.33 

Glaas: 

Normal 0. 199 

Crown 0.16 

Flint 0.12 

Graphite 0.201 

loe 0.5041 

India rubber (Para). 

0.27-O.48 

Alundna (AlsOa) ... 0. 183 

CuiO O.III 

Lead oxide (PbO).. 0.055 

Lod atone 0. 156 

Magneaa 0.222 

Magnetite (Fes04) . 0. 1 68 

Silica 0.I9I 

Soda 0.231 

Zinc oxide (ZnO)... 0.12^ 

Paraffin wax 0.69 

Salt, rock 0.21 

Sand 0.195 

Serpentine 0.25 

Sulphur 0. 180 



Talc 

Tufa 

Vulcanite. 

Wood: 

Fir 

Oak 

Pine. . . . 



LIQUIDS 

Acetic acid 

Alcohol (abaolutc) 

Bcnsol 

Chloroform 

Ether 

Gasoline 

Glycerine 

Hydrochlorie acid. 

Ke oeene 

Naphthalene 

Machine oil 

Mercury 

Olive ou 

Paraffin oil 

Petroleum 

Sulphuric acid 

Sea water 



0.209 

0.33 

0.331 

0.65 
0.57 
0.67 

0.51 

0.70 

0.43 

0.23 

0.503 

0.70 

0.576 

0.60 

0.50 

0.31 

0.40 

0.033 

0.35 

0.52 

0.496 

0.336 

0.94 



Table s. Mean Speciflo Heat of Iron (Cm) Between 8S and t Deg. 

Fahr. (Oberhofler) 



t 


600 

0.127 

1600 

0.170 


800 

0.133 

1800 

0.169 


1000 
0.139 

2000 
0.168 


1200 
0.148 

2250 
0.167 


1400 


Cm 


0.167 


t ; 


2500 


ta 


0.167 







/ 



Tftbl* 7. BpMlAe H«»t of Skit (NftOl) SolntloBS 



The ipBclfle hakt of Mlt lolutioiil Incceasea dovdy with rialiig tem- 
perature. Table 7, due to Gr6bor, gives the apeoifio heat of solutions of 
NaCt for various temperaturas and ooncencrationa. Tha values are prob- 
■U)' mora accurate than those given by SJebel in Table 13. 

For ipecUlo bMt of Kuei see table 28, p, 201. 



TuaiMntUTe of Hlzturaa 

The teuperatUK of a mixture □( weiKht Xfi -f- Mi Ifa. oondstins of Mi lb. 

of a Bubotance at temperature Ji and with specifio heat ei and Mt lb. of a sub- 

■tance at temperature ti with a apeciGo heat ci, is given by the equation 

(■- {Mi<:il,+Mxri,)/(.Mici+At^t). In general. t« - Titci/ZSIt. 

II it be required to raise the temperature of Hi lb. of a BubataDca having 

the specific heat ci from the tei^perature h to !■, the weight M± raquiied of 

a Mioond substance at temperature ti and having a speoifio heat ci la 

II Ml lb. of  lu (eorreq»Ddiiia to Vi rni. ft.) at I d«c. b« mind with W> lb. of the same 

■u (namtpODdinc to Vt ou, ft,) tha preraurs belni eonstsDl, then the tampsrature of 
tha miimra la (, - (.Uiti + MM/Wi + Jlfi) - iCVi + VO/KVi/Ti) + (Vt/T.)ll - 
4H,S, In wMth Ti and Ti ats the abfolula tamperatuiaa. 



CHANQB8 OP STATE EFFECTED BY HEAT 



183 



CHuuigM of 8t»t« Effected by Beat 
Table 8. Freesizig Mixtures 

(The loiTHt temperature that may be produced by a f leenng mixture ie the freesing 

point of the solution) 



Mizturea 



Compo- 
sition, 
parts 
by^ 
weight 



Reduction in 

temperature. 

deg. fahr. 

from to 



Mixtures 



Compo- 
sition, 
parte 

by 
weight 



Reduction in 
temperature, 

deg. fahr. 
from to 



Sodium phosphate.. 

Sal ammoniac 

Diluted nitric add. 

Sodium sulphate... 
Ammonium nitrate. 
Diluted mtric add. 

Bsl ammoniae 

Saltpeter 

Watar 

Sodium carbonate, 
^monium nitrate. 
Water 



Sodium sulphate... 
DQttted nitric add. 

Sodium sulphate. . . 
Saiammomac 



Saltpeter 

Mitne aoid 

Ammonium oiftrate. 
Water 

Sodium phoephate.. 
Diluted nitric add. 

Potannm hydrate. 
Show 

Sulphuric add 

Nitric add 



} 



) 



9 
6 
4 

6 
5 

4 

5 
5 

16 

I 
I 
I 

3 
2 

6 
4 
2 

4 

I 
I 

9 
4 

4 
3 

I 
I 
2 



34.3 

50.0 

50.0 

50.0 
50.0 



21.2 

-13.0 

10.4 

6.8 
-2.2 



50.0 -9.4 



50.0 


3.2 


59.0 


15.8 


32.0 


-38.3 


-2.2 


-40.0 



Sodium chloride 
Snow 

Saltpeter 

Sal ammoniac. . . . 
Water 

Diluted nitric 

add. 
Snow 

Sodium suliphate. . 
Hydrochloric add. 

Sodium sulphate.. 

Saltpeter 

Sal ammoniac. . . . 
Water 

Sodium 0ul]>hate. . 

Diluted nitric 

add 

Sodium chloride. . 
Snow 

Diluted sulphuric 

add. 
Snow 

Caldum chloride. 
Snow 

Caldum chloride.. 
Snow 



I 
3 

I 
I 
I 

I 
I 

8 
5 

8 

5 
5 

16 

5 

4 

I 

I 

1 

I 

3 
2 

2 
I 



32.0 
46.4 

57.2 
50.0 

50.0 

50.0 

32.0 

23.0 

32.0 
32.0 



- 1.6 
-11.2 

-31.0 

- 0.4 
5.0 

S.t 

-0.4 

-41.8 

-27.4 
-43.6 



Table 9. Melting Points of Various Solidi, Deg. rahr. 

(For pure metals, see p. 41) 



AB<9s: 
Bismuth solder. . 200-262 
Brass and bronae 

(about) 1650 

80Cu + 9OZn.... 1845 
90Cu + 8OZn.... 1615 
!pCtt+ 80 Zn.... 1300 

IMU metal 1742 

I08B + 80 Pb 530 

fi08a + 5OPb 400 

S08a + 2OPb.... 388 

f'^nible alloya: 
33Bi + 33Pb + 33Sn. 250 



18Bl + 36Pb+4dSn 
10 Bi+40 Pb+50Sn 

Tin solder 275-3 

Blast-furnace slag. 237D-2 

Borax 1040 

Cast iron, gray 2200 

Cast iron, white 2070 

Chlorides: 

Caldum 1330 

Potasnum 1350 

Sodium 1422 



Enamel colors 1760.0 

India rubber 257.0 

Paraffin 129.2 

Phosphorus 1 1 1 . 2 

Porcelain 2820.0 

Potassium 143.6 

Sodium. 204.8 

Spermaceti 120. 2 

Stearine 122.0 

Steel 2370-2550 

Wrought iron 2460-2640 



184 



HEAT 



Table 10. Malting Points of Eefractoiiei 

C. W. Eanolt, U. 8. Bureau of Standards 



Refractory 


No. of 

aamples 

tested 


Melting 

pointf deg. 

fahr.* 


Refractory 


No. of 

samples 

tested 


Melting 

point, deg. 

fahr.^ 


Fire-clay brick 

Bauxite brick 

Silica brick 

Kaolin ...,,-,---,, 


41 
8 

3 
3 
1 
1 


2830-3140 
2850-3245 
309O-3I00 
3130-3160 
3260 
3310 


Pure alumina 

Chromite briok 

Magnesia briok 

Chromite 




3720 
»90 
3930 
3960 


Bauxite 


Pure lime 


4660 


Bauxite clay 


Pure magnesia 


5070 



* Not reliable to better than 10 deg. fahr. 

The melting point of cristobalite, the stable form of silica is given as 1710 deg. ± 10 
deg. cent, by J. B. Ferguson and H. £. Merwin in the Journal of Science, Vol. 46, 
August, 1918. 



Table 11. Freesinff Points of Liquids at Atmospherie Pressure 



(Deg. fahr.) 



Alcohol (absolute). 

Ammonia 

Aniline 

Bensol 

Carbon trisulphide. . 
Carbon dioxide. . . . 
Chloroform 



148 
108. 

21. 

41. 
171 
110. 

83. 



Calcium chloride (sat. 

sol.) 

Ether 

Glyoerine 

Naphthalene 

Linseed oil 



40 

180 

4 

176 

4 



oU 

Turpentine 

Sulphuric add 

Salt (NaQ) sol., lat. 

Beawater 

Toluene 



25.7 

14.0 

-105 

- 0.4 

27.5 

--I4S 



Mixtures of glycerine and water 
(BoUey) 



Mixtures of alcohol and water 
(P. Beilstein) 



Per cent 

by weight 

of glyoerine 



Speciiio 
gravity 



Freesing 

point, 
deg. fahr. 



Per cent 
by weight 
of aloonol 



Freesing 

point, 
deg. fahr. 



Per cent < 
by weight 
of aloonol 



Freesinc 

point, 
deg. fahr. 



10 
20 
30 
40 
45 
50 

60 



1.0245 
1.0498 
1.0771 
1.1045 
1.1183 
1.1320 

1.1582 



30.2 

27.5 

20.8 

I.O 

-15.2 

-25.6 

Below 

-31.0 



2 
5. 

7. 

9. 
11. 
13 



58 

22 
36 
58 

50 
27 



16.53 
19.09 



30.2 
28.4 
26.6 
24.8 
23.0 
21.2 
17.6 
14.0 



21.7 
23.8 
26.0 
28.0 
30.0 
33.5 
37.3 
41.2 



10.4 
6.8 
3.2 

- 0.4 

- 4.0 
-11.2 
-18.4 
-25.6 



Table 12. 



Preesinff Point, Density, and Speoifle Beat of Calcium 

Chloride Solutions 







(U. S. Bureau of Standards) 






Per cent 

of CaCli 

by 

weight 


Specific 
Gravity 

at 39 
deg. fahr. 


Freesing 

point, 

deg. 

fahr. 


Specific 

^eat 

at 32 

deg. fahr. 


Per cent 

of CaClt 

by 

weight 


Si>eeifio 

Gravity 

at 39 

deg. fahr. 


Fraeaint 

point. 

deg. 

fahr. 


SDOdfio 

heat 

at 32 

deg. fahr. 


14.88 
16.97 
19.07 
21.13 


1.12 
1.14 
1.16 
1.18 


15.8 

8.6 

3.2 

-4.0 


0.799 
0.775 
0.753 
0.733 


23.03 
24.89 
26.77 
28.55 


1.20 
1.22 
1.24 
1.26 


-11.2 
-20.2 
-29.2 
-40.0 


0.714 

0.690 

0.679 

.0.668 



FREEZINQ AND BOIUNQ POINTS 181 

Tabl* IS. ItMtinr Point, Dwuitir, uid lp*eifio HMt of Sodluni 

Chloride Solution! 

(From Siebri'»"Conipen<l ol Mcgh^nical lUfritaftion") 



S'Na^ 


^^; 


Fnadnc 
polDt. 


=c;."" 


Pereent 

of N.a 


Rn-ifin 


point, 


■«• 




















d4.(iAr. 




deg. lahr 


















B 


1 Wl 
























































































































I,«B 


22. 













Table 1^ BoUinc Pointe (Def. t%ia.) »t Atmoapherle Preuure 



131 



Piranihori 



. 3« 



''.-> 



hnffin in I Caldoin ohlorlde (ut.«oL) 3! 

Hekt of Pusioii. Tbe heat of fusion of t. sdid is the heat required in 
B.t.u. to convert 1 lb. of the subatonoe from the solid to the liquid state, with- 
Dul chsDge of temperature. 

Tftbie U. HMt oC rotton, B-bo. por Lb. 



Iraa, white. . 
LaJ 



Tla.. 



TT.SPb+aa.aSa.. 17.0 

T8.«BD + 21.eZD.. 41.3 
e3.H8a + e.i4Za. 31. S 
0T.328ii + S.6SEd. 27. Z 
BritUnlk sieUl (B 
8o + lPb) 13.7 



lipowita'i : 
Koib'i meli 
Wcwd'a me' 



11.1 
. 11.1 





I 

a 


MMhyl ohlDcldi, 


175 

1' 

133 






















CBrboni^suiphide.... 



























TaUe IT. BoldUon of Oum in Wkt«r 






1 (<!•«. fkhr.) - 


U 


» |!1! 


I {deg. fid.r.> - 


32 


68 


.,= 




s.dii 


2.J 


o.Di; 
6:i6 


psLstaE 


4L 

0.053 


D.DID 

> 




&^r*,id;::: 


l.O 



















186 



HEAT 



Tabto 18. Solubilitj of Ammonia in Water (H. MoUiar) 

One pound of water Rt the Kiven ]>re«uree and temperatures abaorbe the foUowing 

weights of ammonia: 



Prespire, 
lb. per 
sq. in. 




Temperatures, deg. fahr. 








* 


32 


60 


80 


100 


120 


140 


160 


180 


200 


220 


240 


260 


260 


300 


2 


0.29 
0.47 
0.70 
0.90 
1.15 

1.71 
2.31 


.154 
.296 
.462 
.607 
.726 

.920 


.086'o.O4O 
.200 128 


.002 
.071 
.164 




















5 


0.026 

\m> 


















10 


.327 
.426 
.539 

.698 
.862 
.992 


0.243 
0.334 
0.423 

0.539 
0.663 
0.776 
0.890 
1.003 


.056 
.106 
.151 

.228 
.302 

.358 
.410 
.470 

.512 
.620 
.727 
.622 


.016 
.057 
.093 

.158 
.215 
.271 
.314 
.363 

.402 
.466 
.563 
.636 














15 


.223 0.166 
.302 0.215 

.406 0.310 


.020 
.046 

.100 
.162 
.195 
.235 
.275 

.309 
.361 
.427 
.509 












20 


.010 

.050 
.090 
.126 
.162 
.197 

.227 
.268 
.323 
.394 










50 


.014 
.046 
.079 
.126 
.135 

.162 
.213 
.262 
.304 








40 


.511 
.604 
.666 
.776 

.894 


0.398 
0.465 
0.528 
0.606 

0.660 
0.794 
0.926 
1.063 


.007 
.035 
.058 
.080 

.106 
.150 
.188 
.224 






50 


.001 




M 






.021' 


70 








.040 

.062 
.099 
.132 
.163 


,003 


80 








.021 


100 










053 


120 












.081 


140 












.111 

















Beat of Vaporiiation (Table 16). The latent heat of vaporisation la the 
quantity of heat in B.t.u. required to convert 1 lb. of a liquid into vapor at 
the same temperature under a conatant external pressure. The latent heat 
depends upon the temperature at which the process takes place. 

For the latent heats of steam at different pressures, see p. 209; and for 
the latent heats of refrigerating media, soo pp. 218, 221 and 222. 

One cubic foot of water at atmospheric pressure and at the temperature I 
will dissolve the volumes of gas (in eu. ft. at 32 deg. fahr. and at atmospherio 
pressure) given in Table 17. 

TBANSMIimiON OF HXAT 

Preliminary Statements. There ^are three methods by which heat 
may be propagated or conveyed from one place to another. 

1. By Conduction. ,In this method heat passes from one body to another 
or from one part of a body to another by contact. It is assumed that the 
warmer molecules impart heat to the colder ones. 

2. By Convection. Heat is carried from place to place by the medium 
with which it is associated. Thus, in a hot-water heating system, heat ie 
carried from the furnace through the building by the water in the ssrstem; in 
a boiler, heat is carried through the mass of water by the currents produced 
by circulation. 

3. By Radiation. A source of heat, as the sun or a fire, gives off energy 
in the form of radiant heat. This energy is assumed to be propagated in all 
directions as a wave motion in the ether, and radiation falling upon a body is 
to some extent absorbed by it. According to the modern theory of es- 
ehanget, all bodies whose molecules are in vibration are sources of radiation. 
If two bodies, one hotter than the other, are placed within an enclosure, there 
is a continual interchange of energy between them. The hotter body A 
radiates more energy than it absorbs, the colder body B absorbs more than 
it radiates. The result is^an equalisation of temperature, but even after tha 
equilibrium of temperature the process of radiation continues, each body 
radiating and absorbing energy. 



TRANSMISSION OF HBAT 187 

Truumisslon ot Hut bj ConVMtlon »ad Conduetlon 

ntraomatift of Hekt TnuumlHlon. In the casea of heat trftnamiHioii 
that usaally occur in prutice — in boilers. coademwiB, the cooling of angilie 
crlinden, etc. — heat is transmitted from one fluid 
to UHtdin tbroush a wall nparatinB the two. 
The character of the process is shown in Fig. 1. 
At ths surface of the plate there is a film ot the 

hot fiuld of indefinits thiokneis. This film offers •<■ i 

a connderable teuatance to the transmisaion, as '" 
shewn by the temperature diflerance d — t'l 
thnush it. A corresponding film on the other 
ride of the plate offers resistance measured by the 
teropersture drop t'l — li. Let Q denotethetotal "u> 
heatinB.t.u. transmitted ini hours throufh opiate 

area of A sq. ft. Then, for film /i, Q - JbiAi 'I 

(h - fi); forths plate. Q - (K/b) At (i'l - Ci); Fm. 1. 

for the Blm /i, - ktAi (Ci - tt). 

The coefficieDts h and kt are the eonductuiflM ot the fllm« /i kod /«, 
iHIwctively, JC is the thermal conductivity of the plate and, analoiousb'. <iC A) 
i> the conduotance of the plate. The reciprocals of these. -vii., 1/Jti, l/hi.h/S, 
are the raiiituiow of the two films and plate, respeettydy. Th* total 
nsistance B to' the flow is the tfum of the separate reaiatanoes, A - (l/fc) + 
D/M + (b/K), MiA the eondnetanee of the two Sims and plate b Ko - 1/S- 
fience, Q - ktAt (h - h). 

If the wall is compoaed of sereral layers ot difterent materials having thick- 
nesses h'. b", b"', etc, and thermiil oonductivitiea K', K", K'". etc., the total 
resiiitance ia fi - (l/fci) + [1/fc.) + (b'/K') + {b-'/K") + {b'"lK"') + 
. . . , and h>- l/R. 

The realstuuM of th« fluid Sim depends upon the kind of fluid and the 
charactar of the motion of the fluid alons the walL The resistance of a film 
ol hot gas i> very high. It has been estimated that in certain cawa 08 per 
cent <rf the available temperature drop is required to [oroe the heat through 
the gaa film. If the hot fluid is saturated steam, condensation insures a film 
of water in contact with the plate and the resistance ia relatively small com- 
t>sred with that of a gas film. The film renistoncB ia eonaideraUy influenced 
by the motion of the fluids along the plates. If the hot gas, ai in a boiler 
tube, is given a high velocity the resulting sweeping action partially destroys 
the film and deorBasea the resistance. The same is true on the water Bids 
of the wall. It is well established that the rate of heat truumluloD is. 
dapandant on the Telocity of the fluid along the plate. 

A layer of eoot or scale on a plate haa the effect of making a compoaile 
wall. The resistanca is increased by b'/K\ where b' is the thickness and K' 
the thermal conductivity of the layer. If ^g is the total conductance for the 
dean plata, the ratio of the heat transmitted to that transmitted through the 
dean plate is 

«'«-k/(^^)-'/('+^) 

The experiments of Clement and Garland {BuXUlin No. 40, Engineering 
Experiment Station, University ot lUinoifl) aSord valuable data on the truu- 
mlialon of baat from ataun to water. A stream of water was made to 
flow at various velocities through a steel tube ot 0.985 in. inside diam. and 
with walla 0.134 in. thick. The tube was surrounded by steam, and the tern* 



188 



HEAT 



perature of the outer wall of the tube was measured by thermo-couples. The 
temperature of the inner wall was calculated from the known conductivity 
of 'the metal composing the tube. The results of one series of tests are shown 
in Table 19. 

Table 19. Transmission of Heat from Steam to Water throtif h 

Steel Tubes 



No. of 
test 


TemperstttroB, deg. f ahr. 


Veloetty 

of 

water, 

ft. polt 

sec 


B.t.u. 
trans- 
mitted 

per min. 

per sq.ft. 


Conduotanoes, B.t.u. 
per sq. ft. per sec. 


of 
Bteam 


of 

outside 

waU 


of 

Insido 

waU 


of 
water, 
mean 


Steam 
film 


Water 
film 


Both 

films 

and wall 




330.2 
330.0 
330.0 
330.2 
330.2 
330.2 


220.0 
229.4 
233.1 
241.8 
257.4 
267.1 


165 
177 
185 
197 
220 
234 


69.0 
70.8 
74.6 
78.07 
89.5 
110.2 


17.13 

14.05 

10.39 

8.06 

4.25 

2.31 


3995 
3756 
3455 
3260 
2672 
2370 


0.606 
0.621 
0.594 
0.614 
0.6II 
0.625 


0.694 
0.591 
0.524 
0.457 
0.340 
0.318 


0.255 
0.246 
0.225 
0.215 
0.185 
0.179 



It appears from these results that the velocity of flow has a marked effect 
on the conductance of the water film and upon the rate of transmission from 
bhe steam to the water. 

Conductance of Fluids. As stated in a preceding pare^aph, the rAte 
of transmission of heat between a fluid and a metal surface depends upon 
the conductance of the fluid film. If h denotes the difference of temperature 
between the fluid and the plate wall, and k the conductance, then Q » kMAh. 
The value of k depends upon the nature of the fluid and also upon the velocity 
of the fluid along the surface. The following values may be taken for the 
conditions stated (k « B.t.u. per sq. ft. per hour per deg. fahr. difference of 
temperature) : 

1. For boiling water k -SOOto 1200 

2. For condensing steam k » 2000 

The experiments of Clement and Qarland show a mean value of 0.61 X 
3600 « 2200, approx. 

3. Water, not boiling: 

If the water is at rest, k = 100. 

If the water is in motion, k will depend upon the velocity. In the ex- 
periments of Clement and Garland k varied from 730 with a velocity of 1.45 
ft. per sec. to 2500 with a velocity of 17.13 ft. per sec. 

4. Air at Rest. Take h as the difference between the temperature of the 
surface and the mean temperature of the air in the room. Then, for 
vertical surfaces, 

k - 0.62 + 0.009^ for A < 20 deg, and k «> 0.385 V^ for A > 20 deg., or 

for A -• 5 10 25 60 100 206 300 400 

k^ 0.62 0.665 0.71 0.86 1.04 1.22 1.45 1.60 1.72 

5. Transmission of Heat from the Surface of a Rotating Cylinder to Air, 
as in flywheels, armatures, etc. According to the experiments of Hinlein, 
for 

Smooth Surfaces (polished copper). 

Velocity w, ft. per sec 20 40 60 80 100 

Conductance A; 0.47 1.07 2.79 3.14 8.30 8.38 

Rough surfaces (duU black, varnished). 

o - 20 40 60 80 100 

k - 0.47 2.49 3.82 3.95 4.60 5.10 



THERMAL CONDUCTIVITIES 



189 



Table 20 TheniiAl Conductivities of Metals 



SulMtanoe 


Xemp., 
deg. 
fahr. 


K 


Substance 


Temp., 
deg. 
fahr. 


K 


Metala: 


64 
212 

32 
212 

64 
212 

64 
212 

64 
212 

64 
212 

64 
212 

64 
212 
129 
216 

64 
212 

64 • 
212 


116.0 

119.0 

10.6 

9.7 

4.7 

3.9 

53.7 

52.2 

222.0 

220.0 

169.0 

170.0 

39.0 

36.6 

34.9 

34.6 

27.6 

26.8 

26.2 

25.9 

20.1 

19.8 


MftgBMiun 
lyferoury. . . 


1 ............ . 


32-212 

32 
122 

64 
212 

64 
212 

64 
212 

64 
212 

64 
212 

63 

64 
212 

32 
212 

64 

212 
64 


92.0 


AlVminUm . . r r - t . r . r , t . . 




3.6 


Aluminum ............. 


Mercury. 


4.6 


Antimony 


Nickel 


34.4 


Antimony. ..,.,.,. 


Nickel 


33.4 


Bismuth 


Platinum 


40.2 


Bismuth 


Platinum 


41.9 


Cadmium 


Silver 


244.0 




Silver. 


240.0 


Copper. 


Tin 


37.6 


Copper 


Tin 


35.0 


OoldT. 


Zinc 


64.1 


Gold 


Zinc 


63.5 


Iron. pure. 


Alloys: 
Brass. 




Iron, pure 


63.0 


Iron, wrought 

Iron, wrouxht 


Constantan (60 Ca. 40 Ni) 
Constantan (eo Ca. 40 Ni) 


13.1 
15.5 


Iron, east 


German nl 
Qerman ■il'^ 


ver 


16.9 


Iron. east. 


irer 


21.5 


Steel (I per oeni C) 

Steel (1 per cent C) 

lead 


Manganin 


84 Cu 
4Ni 

12 Mn 


12.8 
15.2 


Lead 


Platinoid 


14.5 









Table Si. ConduetiTities of Various Insulating Materials 

(Poensgen, Zeit. Ver. DetUach. Ing., Oct. 12, 1012) 
(See also Tables 22 and 23) 



Materials 


Wt., 
lb. per 
cu. ft. 


Xat 

68 deg. 

fahr. 


Materials 


Wt.. 
lb. per 
cu. ft. 


KtLt 

68 deg. 
fahr. 


Cork plate No. 1 

Ck>rk plate No. 5 

Cork plate No. 10 

Cork plate No. 14 


3.8 
11.2 
13.4 
16.6 
21.8 
12.7 

18.5 


0.024 
0.028 
0.031 
0.(»4 
0.038 
0.032 

0.039 


Burnt infusorial earth No. 2 
Burnt infusorial earth No. 3 
Burnt infusorial earth No. 4 
Cork linoleum 


20.8 
22.8 
28.2 
33.4 

27.8 


0.046 
0.044 
0.050 
0.046 


Cork plate No. 16 

Charcoal, bound in plates 
Burqt infusorial enrth 


Cork stone 2.6 in. thick 
with 0.2 in. of cement on 
each side 


0.040 


No. I 















Thermal OonduetlTtty. The resistance of the plate to heat transmission 
is 6/ir, the conductance K/h* The number K in this expression is called the 
thermal conduetiTity of the material of the plate. The thermal conduc- 
tivity of a subetance may be defined as the quantity of heat (B.t.u.) that 
flows in a unit of time (1 hr.) through unit area of plate (1 sq. ft.) of unit 
thickness (1 ft.) having unit difference of temperature (1 deg. fahr.) between 
its faoea. This definition follows from the relation 

Q - KAsit'i - t't)/h, or /C - Qb/Ae{t\ - t't). 

It will be observed that the conductivity K involves an element of length, 
while the oonduotance k does not. 

The thermal conductivity of different materials varies greatly. For 
metals and alloys K is high, while for certain insulating materials, as asbestos, 
Cork, and sOk, K is very low. In general, K varies with the temperature. 
In the case of metals K usually decreases with rising temperature, while for 
most other substances the reverse is true. Tables 20 to 24, ooUeoted from 
various souroes, give values of thermal conductivity. 



.T«bl« S3. Thermal Conductivities of Miscellaseaus Solid Substances 



B....... 


Temp. 

"d^ir- 

t.hr. 












.100 

:g 

1 

si 
ii 

0.064 

i:i 

0.05) 
0.041 
D.0I9 

i:s. 


























 2- «0 
D- 12 


























Migncsia, Iiuid 
























GrspkiM, powdered 

Coarse brickduBt 










v^ 










I0-27S 














Infuionnl eatlh 

Serpeatine (Cornwall).. 




Kisrr4Si«.v..; 


75-260 
50-1 )S 










Firabriok, powtlerod 










^'^ir'!'"':::::::: 


Sli 











































Tabto 13. 


(KUSMlt) 






Weight, 
lb. wr 




,. 1 m 1 », i » 


m \ m 


«U> 




36.0 
ll.i 

41.5 

ii 

3«.0 


0.067 


0.097 
0.046 

0.046 


0.110 
0.052 


0.117 

E 


0.12! 
Cot 428°) 


0.125 
0.073 












^TdSii'^..":!^""."'. 








1 


0.021 


oios: 














































'^^.SiT^i^'":^^;,- 


"■"1 

0.05* 


0.0» 


O.OSJ 


"n'ST' 

















THERMAL COND UCTJ VI TIBS 



191 



Table t4. 


OonduetiTitiM of Liquida and Oaies 




Substance 


Temp., 
deg. 
fahr. 


K 


Substance 


Temp., 
deg. 
fahr. 


K 


Alcohol 


77 
54 
77 
41 
4^59 


0.104 

0.099 

165 

0.081 

0.073 

0.096 

0.103 

0085 

0.086 

0.079 

0.106 

0032 

0.036 

0.033 

00126 

0.0094 


Ammonia 


32.0 

2120 

32.0 

44 6 
32.0 

212.0 
320 
320 
32.0 

2120 
46.0 
450 
320 

212.0 
46.0 

45 


O.OIII 


Aniline 


Ammonia 


00172 


Glycerine 


Carbon monoxide 

Carbon monoxide 

Carbon dioxide 


00121 


Bensd 


00123 


Ether 


00079 


OH, olive 


Carbon dioxide 


0122 


Oil, castor 




Ethylene 


00096 


Oil, paraffin 


63 
55 
55 
77 
63 
52 
77 
32 
32 


Helium 


00062 


OiL petroleum 


Hydrogen 


0775 


OIL tarpentane 


H vdrosen 


00695 


VfM»fline 


Methane 


00156 


Water 


Nitrogen 


00127 


Water 


Nitrous oxide 


00065 


Water 


Nitrous oxide 


0122 


Air 


Nitric oxide 


00101 


Argon 


Oxygen 


0.0136 




^^ "w Ov»» 





The conducti^itiei of air and steam are inven as functions of the tem- 
perature by the relations: K (for air) - 0.01221 (1 + 0.00132 t) and IT (for 
■team) » 0.00882 (1 + 0.00219 0. 

For ( (deg. fahr.) -82 60 100 200 300 

JT (for air) -0.0127 0.0130 0.0138 0.0154 0.0170 

JE (for steam) -0.0095 0.0098 0.0107 0.0127 0.0146 

For t (deg. fahr.) - 400 500 600 700 800 

IT (for air) -0.0187 0.0203 0.0210 0.0235 0.0250 

/: (for steam) -0.0165 0.0184 0.0204 0.0223 0.0242 

Heat TrantmiBiion Botwean Fluids Soparatad by a Plato. The 

following are important examples of heat transmission through plates or tubes. 
(Lucke's "Engineering Thermodynamlos," p. 550): ^ 

Floid giviiig up beat Fluid receiving Examples of heat transmission 

heat 

((a) Liquid Liquid heat exchangers, etc. 

lb) Gas Hot- water radiators; cooling- tower surfaces, 

(c) Boiling liquid Brine coolers; hot-liquid evaporators. 

(a) Liquid Brine coolers in cold-storage rooms; air oool- 

2 Q^^ , era with water or brine coils; economisers. 

(6) Gas Steam superheaters; air-cooled motors. 

I (e) Boiling liquid Steam boilers; direct-expansion ammonia 

y coils. 

((a) Liquid Condensers; feed-water heaters. 

(b) Gas Steam radiators, 

(r) Boiling liquid Vacuum evaporators. 

Let Q — heat transmitted per hour, ka = coefficient of heat transfer « con- 
ductance of wall, with scale, soot, and fluid films, A — area in sq. ft. through 
which transfer is in process, and fim ** mean temperature difference for the 
process. Then Q » koAkm* 

If one of the fluids is condensing or boiling under constant pressure the 
temperature remains constant during the heat transfer. In case 3(c) both 
fluids remain at constant temperature- and hm is simply the difference. In 
all other caaea the temperature of one fluid or of both fluids changes during 
the process. If hi is the initial temperature difference and ^s the final tem* 
perature difference, then the mean temperature difference for the proceaa is 
civen by hm =(^i —hx)/log,ihi/h%)» 



192 HSAT 

Oo«fietont of Btat Trgifwnlialon 

The Tftltie of the coefficient ko depends on a number of oonditioiu, vii.: 
the oharaoter of the fluids, the velocity of the fluids along the separating sur- 
f aoee, the condition of the surface, and the shape of the surface- In general, 
ko is small when one of the fluids is a gas. The following rough values are 
given by Luoke for the cases stated in the preceding paragraph: 

ValuM of ft* (B.t.u. per ho^r per aq. ft, 
Cmo Fluidfl per deg. fahr.) 

1 (o) Liquid^Liquid fiO-75 

1 (6) Uquid— Qm 2-6 

1 (c) Liquid— Boilinc liquid 10-100 

2 QflkS— Liquid, gas, or boiling liquid. . 2-6 

8 (o) Condenung vapor — Liquid 150-350, 1000 under special conditions 

8 (b) Condensing vapor— <3as 2-4 

8 (e) Condensing vapor— Boiling liquid. . . 400-600 

For some of the most important cases the variation of ko with external 
conditions has been investigated. The following is a r^sum6 of some of the 
results. 

1. Trangmiision Between Steam and Water (Condensers, etc.). Ac- 
cording to the exhaustive experiments of Orrok (Trans, A, S, M, B., vol. 32) 
the value of ko depends upon the following factors: 

(o) ko is approximately proportional to the square root of the velocity of 

the cooling water. 
(6) Ad is inversely proportional to the eighth root of the mean difference 

of steam and water temperatures. 

(c) 1^0 depends upon the material of the tube and upon the cleanliness of 
the tube. 

(d) ^ is reduced in a marked degree by the presence of air in the tondenaer. 
Thus if P9 denotes the pressure of the steam alone and pt the total 
pressure ( «p« +'pre8sure of air), then Jbo varies as (p»/pk)*. 

Orrok (1914) gives the following equation as representing the results of 

tests on condensen under various conditions: Jbo - 350 cica(p»/pi)' X y/to, 
in which ci ( » 0.6 to 1.0) is the cleanliness coefficient, and c» a coefficient 
de]>ending on the material of the tubes. For copper, cs -^l.C; for Admiralty 
mixture, 0.98 (oxidised, 0.97); for Munta metal, 0.95; for aluminum bronae, 
0.92. The exponent for (pa/pt) is now taken as 2 instead of 6. w denotes 
the velocity of the water in ft. i>er sec. 

The variation of Jbo with the water velocity has received attention from a 
number of experimenters. The following are some of the relations obtained 
(Trana. A. jS. M. E„ vol. 32): 

8er, Jbo - 520 Vto; Hagemann, 282 \/w\ Josse, 487 ^/w\ Allen, 220 Vv; 

Stanton, 340 ^/wl Orrok, 308 y/iiJo\ Clement and Garland, 270 ^/w. 

Carrier (TVtms. ii. <S. Af. £., vol. 33), gives the following formula as tepre* 
senting the results of tests on condensers: ko » 1/(0.000394 + (0.00255/w)]. 

t. Steam and Boiling Liquids. Where steam coils are used for 
•▼aporation of water or other liquids the following coefficients of trans- 
mission may boused (Hausbrand, "Evaporating, Condensing and Cooling 
Apparatus ") : 

Let d "• diameter of pipe and I « length, both in feet; then ko •■ 1250/\/^. 
This value holds for copper pipe, when the boiling liquid is water. .For 
wrought-iron pipe take 0.75 and lor cast-iron pipe 0.5 of this value. In 
practice, M of theee values should be assumed. ^ 



HEAT CONDUCTANCE TRHOUOH STEAM PIPES 



193 



in the case of thidc, 'viaootu Uquids, the ilie of pipe hM little influence on 
the rate of trsnsmiaaon, and the following values of ko, may be taken: For 
long heating eoOe, 130-150; for short heating ooils, 160)-160; for thin steam 
pipee. 200. 

a. Bteam to Air. Canier (Tram. A. 8. M. B^ vol 33) deduces the fol- 
lowing formula for the ooefficient of transmission under the conditions that 
obtain in hot-blait heating systems: ^ ■*l/[a+(b/tf)], in which w denotes 
the velocity of the air, ft. per min., and a and 6 are constants depending 
on the type of heater. Tests on a Buffalo standard heater with 60 lb. 
steam pressure, gave a ■> 0.0447, h «> 50.66. For Vento cast-iron heaters 
the test showed a«> 0.047, &- 61.a 

CTondiiGtioa of Heat through Steam Pipei. — ^Fipe GoTerings. The 

coefficient of heat transmission through bare steam lApee varies with the 
steam pressure. Assuming the air to be stiil, k^ may be taken as about 2.1 
for low steam pressure (5 or 6 lb. gage), and 3.0 or 3.1 for a pressure of 90 
or 100 lb. gage. Table 25 gives the results of tests by the Johns-Manville 
Co. on heat conduction through bare pipe and pipe with various insulating 
coverings. Outside temperature, 72 deg. fahr. 

Table 16. Heat Conduction through Eare and Covered Steam 

Pipei 

(Johns-Manyille Co.. New York) 

LOW-PBCSBTTBB StBAM PlPfe 



Nature and thioknoM 
of eoveriiic 


Conductaaoe, 

B.t.u. per aq. ft. 

per hr. per deg. 

fabr. 


Heat traoamitted in B.t.u. per aq. ft. per 
hour at steam pressures (persq. in.) of 


30 1b. 


251b. 


50 1b. 


Aflbeatocel, 1 in 


0.564 
0.798 
0.6% 
0.694 
3.000 


77.4 

111.6 

97.2 

96.0 

360.0' 


109.8 127.2 


Air cell. 1 in 


156.0 

. 135 6 

133.2 

576.0 


179.4 


Asbestoe, molded, 1 in 

Aabestoa. indent, 1 in 

Bare pipe 


156.6 
154.2 
876.11 







HiGH-PRKSaUBB BtKAM PlPB 







1001b. 


160 1b. 


200 1b. 


2601b. 


Asbestos: 










Sponge-felted, 1 in 


0.4524 


120.6 


133.8 


142.8 


151.8 


Sponge-felted, 2 in 


0.354 


94.2 


104.4 


111.6 


118.2 


Spon^f elted, 8 in 


0.324 


85.2 


95.4 


102.6 


106.6 


Magnesia, J. M., 1 in 


0.498 


132.6 
119.4 


147.0 


156.0 


166.2 


Magnesia, J. M., li in 


0.450 


132.6 


142.2 


150.0 


Magnesia, J. M., 2 in 


0.378 


100.2 


111.6 


119.4 


126.6 


Bare pipe 


3.000 


1170.0 


1284.0 


1380.0 









SUFBUIBATSD StBAH 





0.452 
0.354 
0.324 
0.498 
0.450 
0.378 
3.000 


At 600 deg. fahr. 


At 600 deg. fabr. 


Asbestos: 

Sp(»ige-lelt«i, 1 in 

t^nge-felted, 2 in 

Sponge-felted, 3 in. ..... . 

Magnesia, J. M., 1 in 

Magnesia, J. M., li in 

F. F. and A. a P. 2 in 

Bars niDe ................ 


193.2 
151.2 
138.6 
211.4- 
192.0 
161.4 
2000.0 


238.8 
187.2 
171.0 
261.6 
237.6 

aoo.o 

3120.0 







194 



BEAT 



Tmnitnlgfion of Beat hj Radiation 

The absorption capacity of a body for radiation is the ratio of the heat 
absorbed to the entire radiation received on the surface of the body. The 
absolute ''black body" absorbs all the radiation received; hence its absorp- 
tion capacity is 1. Bodies that are good absorbers have also hiffh eapasity 
for radiation. Bodies that are good reflectors, as polished steel or silver, 
have correspondingly small absorption capacity and radiating power. Table 
26 gives the relative absorbing, radiating and reflecting properties of certain 
bodies. 

Table S6. Relative Radiating and Reflecting Capacities 



Substance 



Absorbing 
or radiat- 
ing 
capacity 



Reflect- 
ing 
power 



Substance 



Absorbing 
or radiat- 

ing 
capacity 



Refieot- 

ing 
power 



Water 

Marble 

Glass 

Ice 

Cast iron, polished . 
Wrot.iron. polished. 

Mercury 

Zinc 



100 
93-98 

90 

85 

25 

23 

23 

19 



7-2 
10 
15 
75 
77 
77 
81 



Steel, polished 

Tin 

Brass, dead polished . . 

Brass, bright 

Copper, hammered. . . 

Gold. 

Silver, polished 



17 
15 
11 
7 
7 
5 
3 



83 
85 

89 
93 
93 
95 
97 



The Stefan-Boltsmann Law. The radiating power of a body is pro- 
portional to the fourth power of the absolute temperature of the body. This 
law holds exactly for an absolute black body; for other bodies it holds with 
sufficient exactness for practical purposes. 

Let A "■ area of radiating surface, sq. ft., s » time in hours, T «> absolute 
temperature on the Fahrenheit scale, and Q ■> heat radiated in B.t.u. Then 

Q - CAz (T/IQO)* 
The radiation constant C depends on the substance and on the character of 
the radiating surface. For the absolute black body, C » 0.1618. Values of 
C for various substances are given in Table 27. 

Table 17. Radiation Constanta of Various Materials 



Material 



Temp. 

range of 
experi- 
ment, 

deg. fahx, 



Material 



Temp. 

range of 
experi- 
ment, 

deg. fahr. 



Glass, smooth 

Brass, dull 

Lampblack 

Copper, slightly polished 

Wrought-iron, dull, oxidised 

Wrought-iron, clean, bright 

Wrought-iron, highly poushed ... 

Zinc, dull 

Cast iron, rough, highly oxidised. 

lime plaster, rough, white 

Basalt* , 

SUte* 

Humus 



70 


0.154 


TOO-660 


0.0362 


32-100 


0.154 


100-540 


0.0278 


70-670 


0.154 


8S-225 


0.0562 


lOMao 


0.0467 


120-545 


0.034 


105-480 


0.157 


50-195 


0.151 


140-400 


0.120 


140^400 


0.115 


14(MO0 


0.110 



Red sandstone .. . 
Italian marble*... 

Granite* 

Dolomite* 

Qay 

Field soil 

Chalk 

Gravel 

Water 

Ice. 

Gold plate, shining 
but not polished . 



140-400 
140-400 
140-400 
140-400 
14(M00 
140-400 
140-400 
140-400 

140 

32 

70 



10 
095 
0745 
0685 
065 
063 
051 
0481 
0.112 
0.106 

• 

0.082 



* Finished smooth, but not shining. 

The simplest ease of heat radiation is that in which a body having an 
ectemal surface A of nnlform temperature h is enclosed within a second sur- 
face having a uniform temperature b. Let Ct, Ct and C be the radiation 



THERMODYNAMICS 195 

ecMMtuits for the two aorlaces and lor the absolute blaok body, respeotively. 
Then the^heat transmitted by radiation in z hours is 

Q- A*t(!ri/ioo)* - (r,/ioo)*]/[(i/Ci) + (i/co - (i/c)] 

The following example (Dalby, Inst, Af. E.^ Oct., 1909) shows an applica- 
tion of this formula to steam boilers. Let the temperature of the furnace be 
3000 deg. and that of the boiler plate or tubes, 800 deg. fahr., abs. The 
constant C\ of the incandescent carbon may be taken as equal to the constant 
C of the black body, and Cz for iron may be taken as 0.154. The heat radiated 
per sq. ft. of the boundary i)er hour is consequently 

0.154[(3000/100)* - (800/100)*] = 124,100 B.t.u, 

Ray and Kreisinger (Breckenridge, "Study of Four Hundred Steaming 
Tests,'* U. S. Geol. Survey, 1907) have studied the reUtioni between heat 
transmitted by radiation and by convection in a Heine boiler. It was 
found that the heat transmitted by radiation increased with the temperature, 
as indicated by the Stefan law. The ratio of heat received by radiation to 
that received by convection varied from 3 to 15 per cent. 

GXNSEAL PKINCIPLBS OF THKAMODTNAlfflGS 

Notation: 

QtQ ^ quantity of heat absorbed, B.t.u. 

p » absolute pressure, lb. per sq. ft. 
M *» weight of substance under consideration, lb. 
F, » » volume, cu. ft. 

I B temperature, deg. fahr. 

T ^ i -\- 459.6 B absolute temperature. 
C7, fi a internal energy, B.t.u. 
/• i ■" heat content at constant pressure, B.t.u. 
5, » ■» entropy. 

/ » 777.7 « mechanical equivalent of heat. 

A «■ 1/J e reciprocal of mechanical equivalent. 

Cy » specific heat at constant pressure. 

e* » specific heat at constant volume. 

W « external work performed during a change of state. 

In this notation small letters denote magnitudes referred to unit weight 
of the substance, capital letters corresponding magnitudes referred to M units 
of weight. Thus, v denotes the volume of 1 lb., V « Mt^ the volume of M 
lb. Similarly, U » Mu, 8 » Ms, etc. Subscripts are used to indicate 
different states; thus, pi, vi, Tu uii «!• refer to the initial state, pi, vs, Tt, ui, a« 
refer to the final state. Qia is used to denote the heat absorbed by a body 
during the change from state 1 to state 2, and Wn denotes the external work 
done during the same change. 

State of a Substance. — Characteriitie Equationi. Assuming that 
the sabetance under consideration (as air or steam) is homogeneous and of 
uniform density and temperature, and that it is subjected to a uniform 
preesure, the state of the substance is given by the values of p, v, and T. In 
general, two of these three variables may be changed independently , and the 
value of the third will then depend upon the values assigned to these two. 
That is, if 9 and T are taken to vary independently, then p^ f (,v, T). The 
equation that expresses the relation between p, v, and T is called the 
charaeteriitie equation of the substance in question. 

For perfect gaMi the characteristic equation has the aimple form 

pv '^RT. 



• 196 HEAT 



This IB approzimAtely the equation of air, oxygen, nitrogen, and hydrogen. 
For certain gaees, the equation of van der Waals ^ 

BT _£ 

represents quite accurately the states of the substance. The empirical 
equation v — c « {BT/p) — [(1 + 3apH) m/T^\ applies to tuperheatad it«am. 
Any magnitude that depends upon the state of the substance may be used as 
a variable to describe the state. In addition to p, v, and T, the entropy «, 
energy u, and heat content % may be so used, 

Tundamental Lawi of Thermodynftinioi 

TnuoBformstiong of Inergy are subject to two general laws: (1) The 
law of conservation of energy, which may be stated as follows: The total 
energy of an isolated system remains constant and cannot be increased or 
diminished by any ph3rBical process whatever. (2) The law of degradation 
of energy, according to which the result of any transformation of energy is a 
reduction in the quantity of energy available for transformation into useful 
work. 

The following are familiar examples of degradation: Work transformed into heat 
through friction; electrical energy transformed into heat in the conducting ssrstem; 
flow of heat from a body of higher temperature to one of lower temperature; throttling 
or wire-drawing prooeoMs. 

The First Law of Thermodynamics is the conservation law applied to 
the transformation of heat into work, or vice versa. When work is expended 
in producing heat, the quantity of heat generated is equivalent to the work 
done; conversely, when heat is employed to do work, a quantity of heal 
precisely equivalent to the work done disappears. 

The first law is expressed symbolically by the equation W -■ JQ, in which 
W denotes the work and / the mechanical equivalent of heat. The follow- 
ing are the values of the constant / in various units: 

1 gram-calorie » 4 . 184 joules 
1 kg.-calorie ^ 426.65 m.-kg. 
1 B.t.u. = 777.64 ft.-lb. 

For ordinary calculations the values 427 and 778 are suflSciently accurate. 
Another useful relation is 

1 h.p.-hr. « 2546 B.t.u. 

In writing the equations of thermodynamics it is frequently convenient 
to use the reciprocal of J, which is denoted by A; thus A = l/J. 

The Energy Kquation. I'he first law applied to a change of state of a 
substance is expressed by the equation 

JQit - TTii - E« - ifi 

in which Ei denotes the total energy of the substance in the initial state and 
B% the total energy in the final state. The total energy E is made up of the 
internal energy U and the external kinetic energy. The latter comes into 
consideration in the flow of fluids. In case the kinetic energy remains con- 
stant or ■> 0, the energy equation becomes 

Qit - C^j - C^i + AWn 
If the work W arises from the overcoming of fluid pressure, then W « y pdF 
and the equation takes the form 

dQ - <f C7 + ApdV, or Qu - l^i - CTi + A /* 'pdF 

y. 



THERMODYNAMICS 1^ 

The ehancd of energsr depends upon the initial and final states of the system 
only. The external work depends, however, on the rdation between p and V 
during the change of state, that is, upon the path; henoe the heat absorbed 
also depends upon the path. 

If a system passes through a closed eyde of processes and returns to its 
ijiitial state, the change of energy for the cycle is sero; hence for a closed 
eyde the heat absorbed by the system is the equivalent of the eternal work. 
This statement is expressed symbolically by the equation J{Q) •» (TF), where 
iQ) denotes the heat absorbed for the cycle and {W) the net work performed. 
If the change of state is adiabatic, the heat absorbed is sero and the external 
work is gained at the expense of the intrinsio energy of the system. That is. 
Fu - 17» - t/s. 

The Second Law of ThennodyiUbmios is essentially the law of degrada- 
tion of energy. While the first law gives a relation that must be satisfied in 
any transformation of energy, it is the second law that gives information 
regarding the possibility of transformation and the availability of a given form 
of energy for transformation into work. The following is a general statement 
of the second law: No change in a syitam of bodies that takes place of 
itielf can increase the available energy of a system. 

A more concrete statement is that of Kelvin, namely: It is impossible by 
means of inanimate material agency to derive mechanical effect from any por- 
tion of matter by cooling it below the temperature of surrounding objects. 
In effect, Kelvin's statement denies the possibility of deriving work directly 
from the heat contained in the atmosphere. 

The availability of a given quantity of heat energy for transformation into 
work is given by the efficiency of the ideal Carnot engine. Thus, if T 
denote the temperature of the source of heat and T^ that of the refrigerator, or 
coldest body available, then the efficiency is e - (T - To)/!" « 1 - (To/T). 
If beat Q is taken from the source the part Q[l " (To/T^] may be tran^ormeid 
into work under ideal conditions, but the part Q(T»/T) at least must be 
rejected. 

Bntropy. £xi>erience shows that every actual phs^sioal process is irre- 
versible and acoompanied by frictional effects. As a result the actual 
irreversible process is acoompanied by a decrease of the quantity of energy 
available for transformation into work, or, what is the same thing, an increase 
of unavailable energy. The increase of unavailable energy is the product of 
two factors: one is To, the lowest absolute temperature available (usually the 
temperature of the atmosphere), the other is a term of the form Q/T or 
fdQ/T. To this second factor the name increase of entropy is given. 

When the oonoeption of increase of entropy is applied to the system compoaed of all 
the bodies involved in a change, that is, to an irolated ayutem, it appears that the increase 
of entropy is a nieasure of the thermodynamic degeneration produced by the change. 
Aoeording to the law of degradation every natural change is accompanied by thermo- 
djnamie degeneration, therefore it is acoompanied by an increase of entropy. The 
f dlowing important principle is evident: The direction of a process, physical or chemical, 
that ooeiUB of itself is sueh as will bring about an increase of entropy of the ejrstem. This 
principle is tiie foundation of the application of thermodynamics to chemistry. 

The conception of inorease of entropy may be extended to a body not 
isolated but in thermal communication with other bodies. In this case the 
change of entropy is given by the relation 

St -Si »Jti 1p ^ Jtx ~t 



198 HEAT 

in which Q denotes heat absorbed by the body from outside and H heat 
generated within the system through friction. For a reversible friotionlefls 

change, the increase of entropy is simply ^y^^ — . 

The entropy of the body, as thus defined, depends on the state only; hence 
S may be used with p, F, and T as a variable defining the state. For reversi- 
ble friotionless changes, the defining equation gives dQ » TdS; hence the 
energy equation may be written TdS » dU •\- ApdV. 

General Thermodynamic Belations. The first law gives the energy 
equation 

dq = du + Apdv (1) 

the tiecond law gives the entropy equation 

dq * Tds (2) 

A third general equation is obtained by the introduction of a magnitude 
analogous to the energy u and defined by the relation 

t = w -f- Apv (i = C7 + ApV) 
This is called the heat content at constant pressure, for the reason that 
t2 — ii » Qis for a change at constant pressure. By the introduction of 
t, Eq. (1)^ takes the form 

dq '^ di — Avdp (3) 

By various transformations the following relations are derived from these 
three fundamental equations: 

1. Maxwell's thermodynamic relations: 

(y.) . " " ^ (af ) . (d^/r'^Vdr), 

(di).'^ (di), (d;) r " ~ ^ w), 

2. Relations involving specific heats: 

--■ "•(5i^),(lf). 
(a?) r ° ^'' (ar>/ . W) t' ~ "^"^ (wrO , 

3. Relations involving q, u, i, and s: 

dq - c^T + AT ^'ll^ jh dq - e^dT - AT ^|^^ dp 

du^c^t+A^T^^y -D]dt, di«cpdr-^[r(|l)^-,,]dp 



dT 



^(ll)/'"^y-^(l?)p^^ 



The derivatives involved in these relations are found from the characteristic 
equation of the subetance under investigation. Thus, for a perfect gas. 



THBRMOD YNA MTCS 



199 



p. - BT. whence (f|) ^ - f . (|^) 



B — . Substitution of these expres* 

sioDS in the preceding equations gives the following results for gases: 

Cp— Cv  AB 
dq » CvdT + Apdv dq - CpdT — Audp 
du « cwfr rfi « CpdT 

dT dv dT ^ dp 

da^ C9-=- + AB — ^cp -jr — AB — . 
T V T p 

As an szample of the use of the Clauaius relation (t-^)  — AT* (xm^) , oonaider 

J^T' en 

tfas ease of auperheated steam, the equation of which is v — c — — — (1 +3ap^^} -s^' 
=!^iy»<l + ^v\ .rt«n« (^) - 4=!^ (1 +3.pM,.ana 




idr>> 



«'- ^=^^^(x+2-r^+/(r). 



It follows that Cp lot superheated steam Taries with the temperature and also with 
ths pressure. 

Onphic«l SaproMntation. The change of state of a substance may 
be shown graphically by taking any two of the six variables p, V, T, 5, U, I^aa 
independent co-ordinates and drawing a curve to represent the successive 
vilues of these two variables as the change proceeds. While any pair may 
be chosen, there are three systems of graphical representation that are spe- 
cially usef uL 

1. p and V. The curve (Fig. 2) represents the simultaneous values of p 
and V during the change from state 1 to state 2. The area between the curve 

and the axis OV is given by the integral^ ' pdV and therefore represents the 

external work TFu done by the gas during the change. The area included by a 
dosed cycle represents the work of the cycle (as in the indicator diagram of the 
•team engine). 




T 


C 


A 




B 






. A 


2 




D 

















S 



Fio. 2. 



Fig. 3. 



1 T and 8 (Fig. 3). The absolute temperature T is taken as the ordinate; 
the entropy 8 as the abscissa. The area between the curve of change of 

State and the iS-azis is given by the integral J TdSt and it therefore repre- 



si 



eents the heat Qit absorbed by the substance from external sources provided 
there are no irreversible frictional effects. On the T-3 diagram an isothermal 
ia a straight line, as AB, parallel to the jS>axis; a reversible adiabatic is ft 
straight line, aa CD, parallel to the 7-axis. 



200 



HEAT 



In the oaae of internal generation of heat through friction, as in steam tur- 
bines, the increase of entropy is given hyj* — - (see p. 107) and the area 

under the curve represents the heat H thus generated. In this case aaadia- ; 
batic is not a straight line parallel to the T-axis. 

8. Z and 8. In the system of representation 
devised by Dr. MpUier, the heat content / is taken 
as the ordinate and the entropy 8 as the abscissa. 
If on this diagram (Fig. 4) a line of constant pres- 
sure, as 12, be drawn, the heat absorbed during the 
change at constant pressure is given by Qit ■- 1% 
— /i, and this is represented by the line segment 
23. The Molllor diagram is speciiJUbr useful in 
problems that involve the flow of fluids, throttling, 
and the action of steam in turbines. The ad- 
vantage lies in the fact that heat and work are 
represented by line segments instead of areas. A Mollier 
ia given on p. 215, and for ammonia on p. 219. 

PIBnCT GASXB 

Lawi of QaMt. The so-called perfect gases are those that obey very 
closely the laws of Boyle and Gay-Lussao. The two laws are combined in 
the characteristic equations fw >- BT*, pV ■> MRT, in which Riaa, constant 
for any gas. The value of R for a gas is inversely proportional to the molecni- 
lar weight m of the gas and is given by the relation 1544/m. 




for steam 



Since for a perfect gas 



becomes 



a 



AT 



(11).- 



■i — , the general equation (p. 198} 
P 

0; that is, the intemsl energy u is in- 



dependent of the volume and depends on the temperature only. 

Speolflo Haatg. According to the experiments of Regnault and others the 
specific heats Cp and e« of diatomic gases (oxygen, nitrogen, etc.) are practically 
constant for considerable ranges of temperature, and in ordinary applications 
that involve only moderate ranges of temperature they may be taken as con- 
stant. Other gases, as superheated steam, ammonia, and carbon dioxide, 
show a considerable variation of specific heat with the temperature. The 
values of Cp and e« in Table 28 are therefore to be considered as approximately 
correct for the range 32 deg.'-400 deg. fahr. For further discussion of specific 
heats of superheated steam, see p. 212. 

The difference of the specific heats Cp and c« is given by the relation Cp — ci 
*■ AR -• 1.9855/m, or approximately 2/m. The ratio Cp/e^ is denoted by k 
and the value of k for diatomic gases is about 1.4. 

BpeeUlo Weight and Spaeiflc Volume. Referred to standard atmoe. 
pherio pressure and a temperature of 32 deg. fahr., the weight of a cubic fool 
of gas is 0.002788 m lb. and the volume of one pound in cubic feet is 358.65/fa. 
The mol is frequently taken as the unit of weight for gases. The mol is 
defined as m lb. where m denotes the molecular wei^t; thus, for oxygen, 1 
mol «■ 32 lb. For any gas, therefore, the volume of 1 mol at 32 deg. f ahr« 
and atmospheric pressure is 358.65 cu. ft. If M' denotes the weight in xaolt, 
then M ■> Af' m, and the characteristic equation becomes 

oF - 1544 M'T, or A9V - 1.9855 M'T 



PERFECT GASES 



201 



Tli» flpeeffi^ heats re f erred to the mol as the unit of weight are mcp 
■nd fPio», lespeetiTely, and me^ — me« >- 1.0855 ( - 2, approz.) ; mcp • 
L9mk/{k - 1); me, - 1.0855/(Ap - l). 

Taking k - 1.4 for diatomic oases, then approximately me^ • 7, mc« *- 5. 

Tabto S8. Properties of Gaaea 



3 



! 

s 

* 

"3 
I 



MoImu- 
lar 



■A 



HO 



Weight in lb. 

of 1 ou. ft. At 

Atmos. 

prenure 



I. 
§1 



I. 
si 



I 

8 

a 

o 



Spedfio 

Mat 

per lb. 



Specifio 

heat per eu. 

ft. at atmoa. 

Sreifureaod 
2 deg. f abr. 



I 



Bittiim... 
Aifpu, ... 
Air. ..•••■ 
Oqrgea. . . 
Nttroffen.. 




itne 0I- 
ads 

Carbon 

■OBoiide 
H vdro- 
eoloria 

add 

Carbon 

dioiide. . 
Nitrona 

odda.... 
Snlphnr 

dbzide. . 
Ammonia. 
Aeatylene. 
Methjl 

eblorida.. 
Ifsthaae.. 
Bthylenab. 



He 
At 

 • • • • •* 
Oi 

Ha 

NO 

GO 

HQ 

OOi 

NiO 

80t 
NHf 

CaH« 

CHsCl 
CH4 
C«H« 



4.0 
40.0 
29.0 
32.0 
28.0 

2.0 

30.0 



4.0 
39.9 
28.95 



0.0105 
0.1048 
0.0761 
0.0840 
0.0737 



28.08 
2.01610.0052910.00562 



30.04 



28.028.00 



0.0789 to.0638 
0.0734 b.0780 



36. 

44.0 

44. 



536 



.45 

44.00 
08 



044 



64 

17.0 

26.0 



064 



50.5 



06 
17.06 
26.02 

50.47 
16.03 
.03 



028 



I: 



0112 
1112 
0607 
0.0892 
0.0783 




0.1326 
0.0421 
0.0738 



.1786 
.0476 
.0725 

.1407 
0.0447 
0.0780 



.137 

.378 

1 

.105 
.970 



1240 





0.0696^65 



386.0 11.25 

53!34t0.24l 
48.25^ — 
54.99^ 



1.038 
0.960 



I.: 

1.520 

1.522 

2.213 
0.590 
0.899 

1.744 
0.554 
0.969 



2170 
2470 



65.86^3.42 
51.400.23 



0.75 h>.OI31 
0.075*0.0131 
0.1710.0183 
1550.0182 
.1760.0182 
12.44 0.0181 



2310.1650.0183 
55.l4l0.243 0.1720.0180 



42.350.191 
35.090.21 



0.1360.0183 



35.(80.221 



:: 



.1600.0243 0.0185 



24.10|O.1540.123O.O26O 



350D.27( 
24 0.20 



30.590 

96.310.59310.4 
55.08,0.40 0.33 



.1710.0256 



02071.25 
90.50i0.523{0.399|0.0234|0.0178 1 .31 
59.34,0.35QJ0.270|0.024 0.01851.: 



n 



K).032 
025 
029 



0079 
0079 



1.66 
1.66 



0130 1.40 



0130 



1.40 



0130 1.40 
.01291.40 



0.0130 1.40 



0.0126 



0.0130 



1.41 



1.40 
1.31 

0.019811.26 








0265 

019 

024 



1.20 
1.32 
1.20 



Om Mlztorog. liSt V denote the total volume of the mixture, Mi, if t, Aft 
. . . the weiffhtB of the constituent gases, /^i, At, i?i . . . the corresponding 
fss constants, and Bm the constant for the mixture. The partial pressurei 
of the constituents, that is, the pressures that the constituents would have if 
ooeapjing the total volume 7, are pi  MiRiT/V, pi - MiRtT/V, etc. 

Aocxxrding to Dalton's law, the totftl preeaure p of the miatture is the 
sum of the psjrttal lyressures; that is, p "i pi + pi + Pi + . . . Let M « 
ifi + Ifi + Mt + • • • denote the total weight of tiie mixture; then pF » 
ACS.T and Bm - Z{MiRi)/M. Also pi/p - MiBi/MRm, Pi/p - 
MiRt/MBm, etc. 

Let Vi, Vt, Ft» • . • denote the volumes that would be occupied by the 
acostituente at pressure p and temperature T (these are given by the volume 
composition of the gas). Then 7 » 7t + Vi + V| + . . . and the appa- 
rent molecular weight m« of the mixture is m«  X{miVi)/V, Then Bm * 
1544/m,. 

VolanM of 1 lb. at 33 deg. fahr. and atmos. pressure » 858.65/m«. 
Weiclit of 1 Ctt. ft. at 82 deg. fahr. and atmos. pressure • 0.002788mai, 
The spaollle lieftts of the mixture are, respectively 

c, - r(Af<c^)/Af, e^ - ZiMtCH)/M. 



202 HEAT 

In«rg7, Heat Coatent, and Sotropy. II » gM ohangas from an initial 

■tate pi, Vu T\t to a final state pi, Vi, Tt, the following equations hold: 
Ui ^Ui^ Mcv (Tt - Ti) - il(j)iF, - piVi)/(k - l) 
/, - /i - Mcp (Tt -Ti) - ilJfe(j)iri - piFi)/(Jfc - 1). 



5t-5i - M 



[c log.^1 + Afi log* pj - If [c, log.^| - iUJlog.^] 
- M ycp log.— + c. log.^J- 



In general, the energy per unit weight is u » CvT + uo, 

the heat content is t » Cp7 + to, 

and the entropy is « >- c« log T + ilA log « + «o 

= Cp log r — AR log p -f «'o ■» Cp log » + c, log p + *"# 

The two fundamental equations for gases are 

dq - e,4T + Apdv, dq - CpdT - Amjp. 

Special Changes of State 

In the following formal sb the subscripts 1 and 2 refer to the initial and 
final states, respectively. 

1. Constant Volume : pt/pi « Tt/Tu Qu - t/t - t^i - Af c, {t* - <i). 
Qii = A V{pt - pi)/(* - 1). Tf « 0. *,-«,= Mci log,(Tt/Ti), 

1. Constant Pressure : Vi/Fi « ri/ri. TFu « p(Vi- Vi) = AfiJ (<» - «i). 
Qii - Mcp (tt - ti) - ilfclTu/Cib - 1). *,-«!- JIfc, iog,(r»/ri). 

5. Isothermal. (Constant Temperature) : pi/pi •■ Vi/Vu 
Ut -Ui ^ 0. TTi/ « MRT log.(7«/Vi) - piVi log.(F,/Vi). 
Oil - AWit, at - »i - <?ii/r - MAR log.(Vt/V,). 

4. Adiabatic: r,/!ri« (Fi/F,)*--^ - (p«/pi)<* "*>/*. piri*-p«Ff*. 

ilTTw - t^i - C7t « Afc^i - tt). Qit - 0. St - «i -0. 

Wit = (piFi - p»F,)/(fc - 1) - piFi[l - (pt/pi)(*- »)/*I/(fc - 1). 

6. Polytropic. This name is given to the change of state which is repre* 
sented by the equation pF*^ — const. The polytropic curve usually representa 
sufficiently well actual expansion and compression curves in motors and air 
compressors. By giving n different values the preceding changes are mado 
special cases of the polytropic change, thus, 

for n « 1, pr a const. isothermal 

n ^ k, pt^  const. adiabatic 

n B 0, p <- const. constant pressure 

n B 00, v B const. constant volume 

For a polytropic change the specific heat is constant and is given by the 
relation c» »■ Cp(n — fc)/(n — l) ; hence for 1 < n < fc, Cn is negative. This 
is the case in air compression. The following are the principal formulss: 

p,Fi- = ptVt\ Tt/Ti « (Fx/F,)"- ^ = (p«/pi)C»- *)/". 

TFit- (piFi - ptVt)/in - 1) = piFi[l - (pt/pi)("- ^)/"l/(n - l), 

Qu - Mcn(tt -li). 
ATFii : C/i- C^i: dt - * - 1 : 1 - n : A: - n 



PERFECT GASES 



203 



Tabl« M. Adiabatie and Folytrople Ispansioii 







n 


- 






n 


- 




mkm 


1.4 








1.4 








E! 


(AdiA- 

Utic) 


1.3 


1.2 


1.1 


(AdlBr 


1.3 


1.2 


1.1 


PI 








batie) 












7«/Vt- 


Cpi/Pt)»'- 


- 


ri/Ti-Cpi/pOC--')'- 


- 


1.1 


lil70 


1.076 


1.083 


1.090 


1.028 


1.022 


1.016 


1.009 


u 


1.139 


1.151 


1.164 


1.180 


1.053 


1.043 


1031 


1.017 


\3 


1J06 


1.224 


1244 


1.269 


1.078 


1062 


1.045 


1.024 


1.4 


IJ71 


1.295 


1.323 


1358 


1.101 


1.081 


1.058 


1.031 


li 


1.336 


1.366 


1.401 


1.445 


1.123 


1.096 


1.070 


1.038 


1.6 


1.399 


1.436 


1.479 


1.533 


1.144 


1.115 


1.081 


1.044 


U 


1.461 


1.504 


1.557 


1.620 


1.164 


1.130 


1.092 


1.050 


U 


1.522 


1.571 


1.633 


1.706 


1.183 


1.145 


1.103 


1.055 


1.9 


1301 


1.638 


1.706 


1.791 


1.201 


1.160 


1.113 


1.060 


2J 


l.64t 


1.705 


1.782 


1.879 


1.219 


1.174 


1.123 


1.065 


15 


1.924 


2.023 


2.145 


2. MX) 


1799 


1.235 


1.165 


1.087 


3.0 


2.193 


2.330 


2.498 


2.715 


1.369 


1.289 


1.201 


1.105 


3J 


1449 


2.624 


2.842 


3.126 


1.431 


1336 


1.232 


1.121 


4.0 


2.692 


2.907 


3.177 


3305 


1.487 


1.378 


1760 


1.134 


4.5 


2.926 


3.187 


3.500 


3.925 


1326 


1.415 


1.285 


1.147 


5.0 


3.156 


3.449 


3.824 


4.320 


1383 


1.449 


1307 


1.157 


53 


3376 


3.712 


4.142 


4710 


1.627 


1.482 


1.328 


1.167 


M 


3.598 


3.970 


4.447 


5.100 


1.668 


1312 


1348 


1.177 


63 


3.809 


4.218 


4760 


5.463 


1.707 


1340 


1366 


1.186 


IJH 


4.012 


4.467 


5J>58 


5.861 


1.742 


1.566 


1383 


1.194 


7.5 


4J17 


4.710 


5.360 


6.250 


1.778 


1.591 


1.399 


1.201 


0.0 


4.415 


4.950 


5.650 


6.620 


1.811 


1.616 


1.414 


1.206 


9.0 


4.800 


5.420 


6.240 


7.370 


1.873 


1.660 


1.442 


1.221 


10.0 


5.188 


5.885 


6.820 


8.120 


1.931 


1701 


1.468 


1.233 



Construction of Polytropic Cunres (Fig. 5). Through the origin O a 
tine Oil is dra'wii at any convenient angle a with the V-axis. Then a seoond 
line OB is drawn making the angle 

h with the p-axjB, where angle b is ? ^ 

determined by the relation (1 + 
tan 6) « (1 + tan a)». From the 
initial pomt 1 ipi, Vi) io<^te 
points C and Don the axes. Then, 
by drawing 45-des. lines between 
the axes and the auxiliary lines, 
aa shown in the figure, the suo- 
ceniye pointa on the curve, 2, 3, 
^f etc., are obtained. 

Dttsrmination of Kzponent 
2L Lay off successive values of 
P and F, measured at chosen 
points on the curve tinder investi- 
0ition, on logarithmic cross-seo- 




FiQ. 5. — Graphical Construction for 
Polytropic Curves. 



tion paper; or, lay off values of log p and log V on ordinary cross-section 
PAper. If n is a constant, the points will lie io a straight line, and the elope 
of the line gives the value of n. 



204 



HEAT 



If two repiMentatiye points {pi, Vi and pt, Vt) be ohoten, then 

n - Oog pi - log pi)/(log Vt — log Ft). 

Several pain of points should be used in order to test the constancy of n. 

ChuigM of State with Variable Bpeeifle Heat. In case of a consider- 
able range of temperature, as in the internal-combustion motor, the assump- 
tion of constant specific heat is not permissible, and the equations referring 
to changes of state must be suitably modified. Experiments on the specific 
heat of various gases show that the specific heat may be taken as a linear 
function of the temperature: thus, Cv » a + &7*; Cp » a' -f bT. 

From the fundamental equation for gases, dq >» c^T + Apdv, the following 
expressions are found for the change of energy and entropy, respeetively: 

Ut-Vi^ MHTt - Ti) + 0.66 (r,« - Tx*)\ 

& - A - M[a log. (Ti/rO + h{Tt - Ti) + AR log. {Vt/Vi)\. 

For an adiabatic change, , 

Wu = J{Ux - Ut) 

AR log, (pt/pi) ^ (a +AR) \oe,(Ti/Ti) + HTt-Ti) 

AR log, (Vi/Vt) « a log. (Tt/Ti) + h(Ti - Ti) 

Ideal Cycles with Perfect Oaaes 

Oases are used as heat media in several important types of motors. In 
air compressors, air engines, and air refrigerating machines, atmospheric air 
is the medium. In the internal-combustion 
engine the medium is a mixture of products 
of combustion. Motors using gases are oper- 
ated in certain well-defined cycles, which are 
described in the following sections. In the 
analyses given ideal conditions that cannot 
be attained by actual motors are assumed. 
However, conclusions derived from such 
analyses are usually valid for the modified 
actual cycle. 

In the following the subscripts 1, 2, 3, 
etc., refer to corresponding points shown in the figures. The work of the 
cycle is denoted by (IT) and the net heat absorbed by (Q). 

Camot'8 Cycle. The Camot cycle (Fig. 6) 
has historical interest only. It consists of two 
isothermals and two a4iabatics. The heat ab- 
sorbed along the upper isothermal 12 is Qit ^ 
MART log. (Vt/Vi), and the heat transformed into 
work, represented by the cycle area is ii(TF) -> 
Qn[l - (To/T)], 

Hence {W) - MR{T - To) log. (Fi/Ti) 

If the cycle is traversed in the reverse sense, 
Qit » MART ft log. {Vt/V^ is the heat absorbed 
from the cold body (brine), and the ratio Qm A{W) 

- Toi {T - To) is the coefficient of perform- ^^o- 7.— StirUng Cycle. 
ance of the refrigerating machine. 

Stirling and Xricsaon Cyclei. In the Stirling air engine (Fig. 7) the 
adiabatics of the Camot cycle are replaced by constant-volume curves; in ths 
Ericsson engine by constant-pressure curves. By the use of a regenerator the 




FiQ. 6. — Carnot Cycle. 





1 


T 2 


J 


^B 


^3 


1 


!T. 




i 


; 
I 

1 


s 



PERFECT OAS CYCLES 



205 



Itieat Qfi xeieoted dorinc the operation 28 ia ttored And is ghren b«ek to the 
medium during the operation 41. In the ideal caee, Qu *" Q^u henoe the heat 
abaorbed from the eouroe ie Qu * MART log« Vt/Vx, at in the Camot eyoie, 
and the efficiency is identical with that of 
the Camot cyde. 

Air engines of the Stirling and Erioaaon 
type, in which the medium is separated from 
the furnace by a metal wall, have been fail- 
ures, and have been replaced by the inter- 
nal-combustion type, in which the air comes 
into direct contact with the fuel inside of 
the working cylinder. The rapid chemical 
action supported by the medium itself 
makes possible the rapid heating of large ^' 
quantities of air to a very high temperature. 
And by proper cooling of the outside sur- 
face of the metal walls, the deterioration of t 
the metal is prevented even at high temper- 
atures. 

The ideal cycles usually employed for 
internal-combustion engines may be classi- 
fied in two groups: 1. Explosive'— Otto. 2. 
Non-explosive — Diesel, Joule, 




Fig. 8. — Otto Cycle. 



The Otto Cycle (Fig. 8). Adiabatic 
(or polytropic) compression 12 Is followed 
by ignition and rapid heating at constant 
volume, 23. This is followed by adiabatic 

expansion, 34. Assuming compression and expansion to be adiabatic, the 
following relations hold: 

t-l k-\ Jfc-1 






(ft) 



Qm « Afc(ra - T^. 

iW) - JQtJil - {Tx/Tt)] « /Afc,(r, - ^4 - r« + Ti) 

t-l 
Pi\ h 



Efficiency - 1 - g - 1 - (^»J 



*-l 



- 1 - 




If the compression and expansion curves are poly tropics with the same value 
of n, replace Jb by n in the first relation above. In this case, 

iW) -[(Pir,-P4r4) -(ptV,-piFi)]/(n-i) -AfiJ(ri- r4-r,+ rx)/(n-i). 

The maan offootiTO prosaura of the diagram is given by 

P» - «Pi[(Pt/pi) - 11, 
where a has the values given in the following table. 



vt/vx - 8 



8 



10 



13 



14 



16 



(n • 1.4) 


. ... a M 1.70 


1.94 
1.92 
1.90 


3.18 
3.11 
2.08 


3.81 
3.38 
3.26 


3.63 
3.67 
2.61 


3.88 
3.81 
2.74 


8.10 
8.08 
2.94 


.8.81 
8.22 
3.12 


8.60 


fa- 1.8) 


.. .. a "■ 1.09 


3.89 


\W — »m «r/ ...... 

(«-1.2) 


.... a- 1.68 


8.27 



206 



TIE AT 



The Jottlo Oyclo (Fig. 9) oonsUts of two adiabfttica and two oonBtant- 
piesaure lines. The following relations hold: 

Ii^Ti IYj^^"^ IZ^Y'^ (^V^ 
Ti n " \Vt) " \vj " Vpi/ 

(IF) - JMcp(Ti - rj - ^4 + Ti). Efficiency - iW)/JQu « 1 - (Ti/Tt). 
For the use of the Joule cycle in refrigeration, see p. 227^ 





Fio. 9. — Joule Cycle. 

The Diesel Cycle. In the Diesel oil engine air is compressed to a pressure 
of about 600 lb. per ^. in. Fuel is then injected into the air and, as the tem- 
perature is above the ignition point, burns at nearly constant pressure (23, in 
Fig. 10). Adiabatic expansion of the products of 
combustion is followed by exhaust and suction of 
fresh air, as in the Otto cycle. 

The work obtained is 




(W) « JM[cp{Tn - r,) - cCr* - Ti)], 
and the efficiency of the ideal cycle is 
1 - [(^4 - Ti)/kiTt - r.)]. 
Air Compreeelon. It is assumed that the o 

compressor works under ideal conditions without pj^^ jq^ Diesel Cycle. 

clearance and without friction losses. If the com- 
pression from piio pt (Fig. 11a) follows the law pV* » const., the work repre- 
sented by the indicator diagram is 

W - niptVt - PiVi)/in - 1) - npiViKpt/pi)^'"-^^^'' - l]/(n - 1). 

The temperature at the end of compression is given by Tt/Ti — 
(Pi/pi)^**""^^/**' The work W is smaller the smaller the value of n, and to 
reduce n from the adiabatic value 1.4 is the office of the water jacket. 
Under usual working conditions, n is about 1.3. 

When the pressure pt is high it is advantageous to divide the process into 
two or more stages and cool the air between the cylinders. The saving 
effected is best shown on the TS plane (Fig. 1 16). With single-stage compres- 
sion, 12 represents the compression from pi to pi, and if the constant-pressure 
line 23 is drawn cutting the isothermal through point 1 in point 3, the area 
1'1233' represents the work W. When two stages are used, 14 represents the 
compression from pi to an intermediate pressure- p\ 45 cooling at constant 
pressure in the intercooler between the cylinders, and 56 the compression in 



VAPORS 



207 



the second stage. The area under 14663 representa the work of ibe two stages 
and tha area 2450 the saving effected by compounding. This saving is a 
mf>.TiTTiiiin when Ta «- TV and this is the case when the intermediate pressure 

j/ is given by p' *- y/pipt. 
The total work in two-stage compression is 

n pxVx Kp'/pi)^'*-^^'''* + (p,/jO^""*^''" - 21 /in - 1). 





3 



Fio. 11a. 



Fia. 116. 



Air-compressor Cycle. 

VAPORS 

Qmmnl Chanu>tarUtloi of Vapors. Let a gas be compressed at con- 
stant temperature; then, provided this temperature does not exceed a certain 
critical value, the gas begins to liquefy at a definite pressure, which depends 
upon the temperature. At the beginning of liquefaction, a unit weight of gas 
will also have a definite volume v^\ depending on the temperature. In Fig. 12, 
AB represents the compression and the point B gives the saturation pressure 
and volume. If the compression is continued the pressure remains constant 
with the temperature, as indicated by BC, until 
at C the substance is in the liquid state with 
the volume v^ i 

The curves v^'and v" giving^the volumes for 
various temperatures at the end and beginning 
of liquefaction, respectively, may be called the 
Umit cuires. A point B on curve v'' repre- 
sents the state of saturated vapor; a point C 
on the curve v' represents the liquid state; and 
a point M between B and C represents a mix- 
ture of vapor aiid liquid of which the part x b 
MC/BC is vapor and the part 1 — a: «- BM/BC 
is liquid. The ratio x is called the quality Of < 
the mixture. The region between the curves 
v' and v^' is thus the region of liquid and vapor 
mixtures. The region to the right of curve v" is the region of superheated 
Tapor. The curve v" dividing these regions represents the so-called satu- 
rated vapor. 

For saturated vapor or a mixture of vapor and liquid, the pressure is a 
function of the temperature only, and the volume of the mixture depends upon 
the temperature and quality x. That is, p « /(0> « » ^(<« s;). 

For the vapor in the superheated state the volume depends on pressure and 
temperature [v » Fi(p, Q], and these may be varied independently. 




Fio. 12. 



208 tTBAT 

Orltle4l 8tetM. ItUiet«mpsrfttuNolllwBuliMBboTe«dBfinitat«mp«n- 
tora tt e«Uad ths erltle»l t*mp«r»ttir«, the (u oannot be liquefied by 
eoaprenion klone. The MtorAtloo preMun oorreapoadiBg to It ii tbe 
erltic*! prauure uid ta denoted by pi,. At the critical state the limit eurree 
** and t" merge; hence for tempereturee above b it ia impoiiible to have a 
mixture of vapor and liquid. Table 30 gives the oritiaal data for variom 
Kaaee; also the boiline temperature h oorreapoadiiig to abnospheric pressure. 

Tftble W. Oritleftl Dste tor Various Ouas 



Thamwl Prop«rtl«i of SktorsUd Tftpors Mtd at Vapor uut UqtUd 

Hlzturss 
KotMlon: 

t*  volume in cu. ft, of 1 lb. of liquid. 

■" ~ volume in cu. ft. of 1 lb. of saturated vapor, at given tamperature. 

c' — speciGo heat of liquid. 

«" — specific heat of saturated vapor, at given temperature. 

r X latent heat, or heat required to vaporiia 1 lb. of liquid at given 

constant preuure and temperature. 
AL — Aplv" —>')■■ external latent heat, i.e., the heat equivalant of 
the external work performed during vaporisatidti. 
t ~ r ~ Aplv" - «') - internal latent heat. 
>', i" — heat content of liquid and saturated vapor, respectively. 
v'. u" - internal energy of liquid and aaturated vapor, reapeatively. 
t' — entropy of the liquid. 
(" — entropy of saturated vapor. 
For a unit weight (I lb.) of saturated vapor the following ralatioiM etlrt: 

i" -i' +r. u" - It' + i. .< - f't-dT/T. t"-i' + (r/T). 

r/T — A(t" — v*) dp/dt (CUpeyroD'i equation), the derivative dp/dt being 
determined from the relation p — /(O between l«mparature and pressure at 
saturation. 

For a unit weight of mixture of vapor and liquid, quality x, theae relations 
become » -i' + sr, u—u'+xl, i - t' + (itr/T); 
olw t - .' + i(." - O. 

Tables of TbamMtl Properties of Tapora 

W«t<r Vapor. The experimental data relating to the propertlaa of watsr 
vapor have been correlated by Marks aod Davit; and the values given in the 
Marks and Davis tables may be accepted as staodard at t^e present time. 



SATURATSD STEAM 



209 



Tftbto 81. PnqiMrtiM off BfttonMil StaMB 

Coadennd from the Steam Tables of Marks and Daris by parmissloii of iha pttbliib«nb 

Longmans,. Qreen and Co. 



AiM. 

mi., 
m^ 

9 

1 
2 

5 
4 


Temp.. 

dec. 

fahr.. 

1 


8p. ToL, 

ou.fi. 

per lb.. 


Density, 
lb. per 
ou.It.. 

1/t" 


Heat 
of the 
liquid, 

i' 


Latent 
heat of 
erap.. 

r 


Heat 

oontent 

of steam. 


Internal 
energy 
(B.t.u.) 
evap., 


Enttopy 


Water, 


Evap., 
r/f 


101.0 
126.15 
141.52 
153.01 


333.0 

173.5 

118.5 

90.5 


0.00900 
0.00576 
0.00845 
0.01107 


69.8 

94.0 

109.4 

120.9 


1034.6 
1021.0 
1012.3 
1005.7 


1104.4 
1115.0 
1121.6 
1126.5 


972.9 
956.7 
946.4 
938.6 


0.1327 
0.1749 
0.2000 
0.2198 


1.7431 
1.6840 
1.6416 


5 
6 

7 
• 
9 


162.28 
170.06 
l».85 
16.86 
188.27 


73.33 
61.09 
53.56 
47.27 
42.36 


0.01364 
0.01616 
0.01867 
0.02115 
0.02361 


190.1 
137.9 
144.7 
150.8 
156.2 


1000.3 
995.8 
991.8 
988.2 
985.0 


1190.5 
1133.7 
1136.5 
1139.0 
1141. 1 


932.4 
927.0 
922.4 
918.2 
914.4 


0.2348 
0.2471 
0.2579 
0.2673 
0.2756 


1.6084 
1.5814 
1.5582 
1.5380 
1.5202 


W 
II 
12 

14 
M.7 


193.22 
197.75 
201.96 
205.87 
209.55 
212.00 


38.38 

35.10 
32.36 
30.03 
28.02 
26.79 


0.02606 
0.02849 
0.03090 
0.03330 
0.03569 
0.03732 


161.1 
165.7 
169.9 
173.8 
177.5 
180.0 


962.0 
979.2 
. 976.6 
974,2 
971.9 
970.4 


1143.1 
1144.9 
1146.5 
1148.0 
1149.4 
1150.4 


910.9 
907.8 
904.8 
902.0 
099.3 
097.6 


0.2832 
0.2902 
0.2967 
0.9025 
0.9081 
0.3118 


1.5042 
1.409S 
1.4760 
1.4639 
1.4523 
1.449 


15 
tt 
17 

N 
» 


213.0 
216.3 
219.4 
222.4 
225.2 


26.27 
24.79 
23.38 
22.16 
21.07 


0.09006 
0.04042 
0.042n 
0.04512 
0.04746 


181.0 
184.4 
107.5 
190.5 
193.4 


969.7 
967.6 
965.6 
963.7 
961.8 


1150.7 
1152.0 
1153.1 
1154.2 
1155.2 


096.8 
094.4 
892.1 
889.9 
867.8 


0.3133 
0.3IO 
0.3219 
0.3273 
0.3315 


1.4410 
I.43II 
1.4215 
1.4127 
1.4045 


2» 
21 
22 
39 
2« 


228.0 
230.6 
233.1 
235.5 
237.8 


20.00 
19.18 
18.37 
17.62 
16.93 


0.04980 
0.05213 
0.05445 
0.05676 
0.05907 


196.1 
198.8 
201.3 
203.8 
206.1 


960.0 
958.3 
956.7 
955.1 
953.5 


1156.2 
1157.1 
1158.0 
1158.8 
1159.6 


885.8 
863.9 
882.0 
880.2 
878.5 


0.335S 

0.3393 
0.3430 
0.3465 
0.3499 


1.3965 
1.3887 

1.3139 
1.3690 


IS 
K 

r 

21 
21 


2«0.l 
242.2 
244.4 
246.4 
248.4 


16.30 
15.72 
15.18 
14.67 
14.19 


0.0614 
0.0636 
0.0659 
0.0662 
0.0705 


208.4 
210.6 
212.7 
214.8 
216.8 


952.0 
950.6 
949.2 
947.8 
946.4 


1160.4 
1161.2 
1161.9 
1162.6 
1163.2 


876.8 
875.1 
873.5 
872.0 
870.5 


0.3532 
0.3564 
0.3594 
0.3623 
0.3652 


1.9604 
1.3542 
1.3483 
1.3425 
1.3367 


21 
91 
12 
13 
14 


250.3 
252.2 
254.1 
255.8 
257.6 


13.74 
13.32 
12.93 
12.57 
12.22 


0.0728 
0.0751 
0.0773 
0.0795 
0.0818 


218.8 
220.7 
222.6 
224.4 
226.2 


945.1 
943.8 
942.5 
941.3 
940.1 


1163.9 
1164.5 
1165.1 
1165.7 
1166.3 


869.0 
067.6 
866.2 
864.8 
863.4 


0.3680 
0.3707 
0.3733 
0.3759 
0.3784 


1.3311 
1.3257 
1.3205 
1.3155 
1.3107 


SS 

3S 


259.3 
261.0 
262.6 
264.2 
265.B 


11.89 
11.58 
11.29 
11.01 
10.74 


0.0041 
0.0863 
0.0886 
0.0908 
0.0931 


227.9 
229.6 
231.3 
232.9 
234.5 


938.9 
937.7 
936.6 
935.5 
934.4 


1166.8 
1167.3 
1167.8 
1168.4 
1168.9 


862.1 
860.8 
859.5 
858.3 
857.1 


0.3808 
0.3832 
0.3855 
0.3877 
0.3899 


1.3060 
1.3014 
1.2969 
1.2925 
1.2882 


41 
41 
42 
« 
44 


267.3 
260.7 
270.2 
271.7 
273.1 


10.49 

10.25 

10.02 

9.80 

9.59 


0.0953 
0.0976 
0.0998 
0.1020 
0.1043 


296.1 
237.6 
239.1 
240.5 
242.0 


933.3 
932.2 
931.2 
930.2 
929.2 


1169.4 
1169.8 
1170.3 
1170.7 
1171.2 


855.9 

854.7 
853.6 
852.4 
851.3 


0.3920 
0.3941 
0.3962 
0.3982 
0.4002 


1.2841 
1.2800 
1.2759 
1.2720 
1.2681 


41 
47 
41 
# 


274.5 
275.8 
277.2 
278.5 
279.8 


9.39 
9.20 
9.02 
0.84 

0.67 


0.1065 
0.1067 
0.1109 
0.1131 
0.1153 


243.4 
244.8 
246.1 
247.5 
248.8 


928.2 
927.2 
926.3 
925.3 
924.4 


1171.6 
1172.0 
1172.4 
1172.8 
1173.2 


850.3 
849.2 
848.1 
M7.1 
846.1 


0.4021 
0.4040 
0.4059 
0.4077 
0.4095 


1.2644 
1.2607 
1.2571 
I.2S36 
1.2SQ2 



210 



MB AT 



T»bl« 81* Propd rt iei of Saturated Steam— (oonitnMd) 

CoDdenMd from the Steam Tables of Marka and Davis by permiMion of the pabli«lMri» 

LongmAns, Green and Co. 



Abe. 

piee.t 

lb.. 



Temp., 

deg. 

fahr., 

f 



8p. voL 
cu. ft. 
per lb., 



Density, 
lb. per 
eu. It., 



Heat 
of the 
liquid. 



Latent 
heat of 
evap., 



Heat 
content 
of steam, 



vr 



Internal 
energy 

(B.t.u.) 
evap., 



Entropy 



Water, 



Evap., 
t/T 



SI 
52 
53 
54 

55 

56 
57 
56 

59 

60 
61 
62 
63 
64 

65 
66 
67 
66 
69 

70 
71 
72 
73 
74 

75 
76 
77 
76 
79 

60 
61 
62 
63 
64 

65 
86 
67 
66 
69 

90 
91 
92 
93 
94 

95 
96 
97 
96 
99 



261.0 
262.3 
283.5 
284.7 
265.9 

267.1 
266.2 
269.4 
290.5 
291.6 

292.7 
293.8 
294.9 
295.9 
297.0 

296.0 
299.0 
300.0 
30t.O 
302.0 

302.9 
303.9 
304.8 
305.8 
306.7 

307.6 
306.5 

309.4 
310.3 
311.2 

312.0 
312.9 
313.6 
314.6 
315.4 

316.3 
317.1 
317.9 
316.7 
319.5 

320.3 
321.1 
321.6 
322.6 
323.4 

324.1 
324.9 
325.6 
326.4 
327.1 



8.51 
6.35 
6.20 
8.05 
7.91 

7.78 
7.65 
7.52 
7.40 
7.26 

7.17 
7.06 
6.95 
6.65 
6.75 

6.65 
6.56 
6.47 
6.38 
6.29 

6.20 
6.12 
6.04 
5.96 
5.89 

5.81 
5.74 
5.67 
5.60 
5.54 

5.47 
5.41 
5.34 
5.26 
5.22 



5 
5 

5 
5 

4 



16 
10 
05 
00 
94 



4.69 
4.64 
4.79 
4.74 
4.69 

4.65 
4.60 
4.56 
4.51 
4.47 



0.1175 
0.1197 
0.1219 
0.1241 
0.1263 

0.1285 
0.1307 
0.1329 
0.1350 
0.1372 

0.1394 
0.1416 
0.1436 
0.1460 
0.1462 

0.1503 
0.1525 
0.1547 
0.1569 
0.1590 

0.1612 
0.1634 
0.1656 
0.1678 
0.1699 

0.1721 
0.1743 
0.1764 
0.1786 
O.K 





0.1915 

0.1937 
0.1959 
0.1960 
0.2001 
0.2023 

0.2044 
0.2065 
0.2087 
0.2109 
0.2130 

0.2151 

o.2in 

0.2193 
02215 
0.2237 



1629 
1651 
1673 
1694 



250.1 
251.4 
252.6 
253.9 
255.1 

256.3 
257.5 
258.7 
259.8 
261.0 

262.1 
263.2 
264.3 
265.4 
266.4 

267.5 
268.5 
269.6 
270.6 
271.6 

272.6 
273.6 
274.5 
275.5 
276.5 

277.4 
278.3 
279.3 
260.2 
281.1 

282.0 
282.9 
283.8 
284.6 
265.5 

286.3 
287.2 
286.0 
268.9 
289.r 

290.5 
291.3 
292.1 
292.9 
293.7 

294.5 
295.3 
296.1 
296.6 
297.6 



923.5 
922.6 
921.7 
920.8 
919.9 



919 
916, 
917 
916. 
915 




2 

m 

5 

7 



914.9 
914.1 
913.3 
912.5 
911.8 

911.0 
910.2 
909.5 
906.7 
906.0 

907.2 
906.5 
905.6 
905.1 
904.4 

903.7 
903.0 
902.3 
901.7 
901.0 

900.3 
699.7 
699.0 
698.4 
697.7 

697.1 
696.4 
895.6 
695.2 
894.6 

893.9 
893.3 
892.7 
892.1 
891.5 

890.9 
890.3 
689.7 
889.2 
886.6 



1173.6 
1174.0 
1174.3 
1174.7 
1175.0 

1175.4 
1175.7 
1176.0 
1176.4 
1176.7 

1177.0 
1177.3 
1177.6 
1in.9 
1176.2 

1178.5 
1178.8 
1179.0 
1179.3 
1179.6 

1179.8 
1180.1 
1180.4 
1180.6 
1180.9 

1181.1 
1161.4 
1161.6 
1181.8 
1182.1 

1162.3 
1182.5 
1182.8 
1183.0 
1163.2 

1183.4 
1183.6 
1183.8 
1184.0 
1184.2 

1184.4 
1164.6 
1164.8 
1185.0 
1185.2 



1185 
1165 
1165 
1186 
1186 



845.0 
844.0 
643.1 
842.1 
841.1 

840.2 
839.3 
836.3 
837.4 
636.5 

835.6 
834.6 
633.9 
833.1 
832.2 

831.4 
830.5 
629.7 
828.9 
828.1 

827.3 
826.5 
825.6 
625.0 
824.2 

823.5 
622.7 
822.0 
821.3 
820.6 

819.6 
819.1 
616.4 
817.7 
817.0 

816.3 
815.6 
615.0 
814.3 
813.6 

613.0 
612.3 
811.7 
811.0 
610.4 

809.7 
809.1 
808.5 
807.9 
807.2 







0. 



4113 
4130 
4147 
4164 
4160 



0.4196 
0.4212 
0.4227 
0.4242 
0.4257 







0. 



4272 
4287 
4302 
4316 
4330 



0.4344 
0.4358 
0.4371 
0.4385 
0.4396 



0. 

0. 
0. 
0. 

0. 
0. 
0. 
0. 
0. 



4411 
4424 
4437 



4462 

4474 
4467 
4499 
4511 
4523 



0.4535 
0.4546 
0.4557 
0.4568 
0.4579 

0.4590 
0.4601 
0.4612 
0.4623 
0.4633 





0. 
0. 
0. 

0. 
0. 
0. 





4644 
4654 
4664 
4674 

A£tkA 

4704 
4714 
4724 
4733 



1.2466 
1.2435 
1.2402 
1.2370 
1.2339 

1.2309 
1.2278 
1.2248 
1.2218 
1.2109 

1.2160 
1.2132 
1.2104 
1.2077 
1.2QS0 

1.2824 
1.1996 
1.1972 
1.1946 
1.1921 

1.1896 
1.1672 
1.1840 
1.182S 
1.1601 

1.1778 
1.1753 
1.1732 
1.1710 
1.1667 

1.1665 
1.1644 
1.1623 
1.1602 
1. 1561 

1.1561 
1.1540 
1.1520 
I.I50O 
1.1461 

1.1461 
I 1442 
1.1423 
1.1404 
1.1365 

1.1367 
1.I3M 
1.1330 
1.1312 
1.1295 



SATURATED STEAM 



211 



Tftbl« SI. ProptrtiM of Saturfttad Stoun — (eonHnuid) 

Oondafiied from the Steam Tables of Marks and Davis by iiermisaion of the pfubUthem, 

Longmans, Green and Co. 



AJbu. 

r 



Temp., 

fshr., 

t 



8p.voL, 
cu. ft. 
per lb.. 



Density 
lb. per 
cu. It., 



Heat 
of the 
liquid. 



Latent 
heat of 
evap., 



Heat 
content 
of steam, 



:*f 



Internal 

energy 

(B.t.u.) 

evap., 



Entropy 



Water, 



Bvap., 
r/T 



in 

KB 
104 

m 

166 

110 
112 
114 

n« 

116 

120 
122 
124 
126 
120 

130 
132 

m 

136 
136 

140 
M2 
144 
146 
MS 

ISO 

m 

154 
156 
150 



327.8 
329.3 
330.7 
332.0 
333.4 

334.8 
336.1 
337.4 
338.7 
340.0 



4.429 
4.347 
4.268 
4.192 
4.118 

4.047 
3.978 
3.912 
3.848 
3.786 



341.3 


3.726 


342.5 


3.668 


343.8 


3.611 


345.0 


3.556 


346.2 


3.504 


347.4 


3.452 


348.5 


3.402 


349.7 


3.354 


350.8 


3.306 


352.0 


3.263 


353.1 


3.219 


354.2 


3.175 


355.3 


3.133 


356.3 


3.092 


K7.4 


3.052 



358.5 


3.012 


359.5 


2.974 


360.5 


2.936 
2.902 


361.6 


362.6 


2.868 



0.2258 
0.2300 
0.2343 
0.2386 
0.2429 

0.2472 
0.2514 
0.2556 
0.2599 
0.2641 

0.2683 
0.2726 
0.7769 
0.2812 
0.2854 

0.2897 
0.2939 
0.2981 
0.3023 
0.3065 

0.3107 
0.3150 
0.3192 
0.3234 
0.3276 

0.3320 
0.3362 
0.3404 
0.3446 
0.3488 



296.3 
299.8 
301.3 
302.7 
304.1 

305.5 
306.9 
306.3 

309.6 
311.0 

312.3 
313.6 
314.9 
316.2 
317.4 

318.6 
319.9 
321.1 
322.3 
323.4 

324.6 
325.8 
326.9 
328.0 
329.1 



330. 
331. 
332. 
333. 



334.6 



888.0 
686.9 
865.8 
884.7 
863.6 

882.5 
861.4 
880.4 
879.3 
678.3 

877.2 
876.2 
875.2 
874.2 
873.3 

872.3 
871.3 
870.4 
669.4 
868.5 

867.6 
866.7 
865.8 
864.9 
864.0 

863.2 
862.3 
861.4 
860.6 
859.7 



1186.3 
1186.7 
1187.0 
II87.4 
1167.7 

1188.0 
1188.4 
1188.7 
1169.0 
1189.3 

1189.6 
1189.8 
1190.1 
1190.4 
1190.7 

1191.0 
1191.2 
1191.5 
1191.7 
1192.0 

1192.2 
1192.5 
1192.7 
1192.9 
1193.2 

1193.4 
1193.6 
1193.8 
1194.1 
1194.3 



806.6 
805.4 
804.2 
803.0 
601.9 

800.7 
799.6 
796.5 
797.4 
796.3 

795.2 
794.2 
793.1 
792.0 
791.0 

790.0 
789.0 
786.0 
787.0 
786.0 

785.0 
764.1 
783.2 
782.2 
781.3 

780.4 
779.4 
776.5 
777.6 
776.7 



0.4743 
0.4762 
0.4780 
0.4798 
0.4816 

0.4834 
0.4852 
0.4869 
0.4886 
0.4903 

0.4919 
0.4935 
0.4951 
0.4967 
0.4982 

0.4998 
0.5013 
0.5028 
0.5043 
0.5057 

0.5072 
0.5066 
0.5100 
0.5114 
0.512^ 

0.5142 
0.5155 
0.5169 
0.5162 
0.5195 



1.1277 
1.1242 
1.1208 
1.1174 
1.II4I 



1106 
1076 
1045 
1014 



1.0964 

1.0954 
1.0924 
1.0695 
.1.0865 
1.0637 

1.0609 
1.0782 
1.0755 
1.0728 
1.0702 

1.0675 
1.0649 
1.0624 
1.0599 
1.0574 

1.0550 
1.0525 
1.0501 
1.0477 
1.0454 



MO 


363.6 


2.834 


0.3529 


335.6 


858.8 


1194.5 


775.8 


0.5208 


1.0431 


K2 


364.6 


2.801 


0.3570 


336.7 


858.0 


1194.7 


775.0 


0.5220 


1.0409 


164 


365.6 


2.769 


0.3612 


337.7 


857.2 


1194.9 


774.1 


0.5233 


1.0367 


m 


366.5 


2.737 


0.3654 


336.7 


856.4 


1195.1 


773.2 


0.5245 . 


1.0365 


MS 


367.5 


2.706 


0.3696 


339.7 


855.5 


1195.3 


772.4 


0.5257 


1.0343 


no 


368.5 


2.675 


0.3738 


340.7 


854.7 


1195.4 


771.5 


0.5269 


1.0321 


172 


369.4 


2.645 


0.3760 


341.7 


853.9 


1195.6 


770.7 


0.5281 


1.0300 


H! 


37D.4 


2.616 


0.3822 


342.7 


853.1 


1195.8 


769.6 


0.5293 


1.0278 


US 


371.3 


2.508 


0.3664 


343.7 


852.3 


1196.0 


769.0 


0.5305 


1.0257 


m 


372.2 


2.560 


0.3906 


344.7 


851.5 


1196.2 


768.2 


0.5317 


1.0B5 


5 


373.1 


2.533 


0.3948 


345.6 


850.8 


1196.4 


767.4 


0.5328 


1.0215 


102 


374.0 


2.507 


0.3969 


346.6 


650.0 


1196.6 


766.6 


0.5339 


1.0195 


114 


374.9 


2.461 


0.4031 


347.6 


849.2 


1196.8 


765.8 


0.5351 


1.0174 


Ml 


375.6 


2.455 


0.4073 


348.5 


846.4 


1196.9 


765.0 


0.5362 


1.0154 


tt6 


376.7 


2.430 


0.4115 


349.4 


847.7 


1197.1 


764.2 


0.5373 


1.0134 


a 


377.6 


2.406 


0.4157 


350.4 


846.9 


1197.3 


763.4 


0.5384 


1.0114 


in 


378.5 


2.381 


0.4199 


351.3 


846.1 


1197.4 


762.6 


0.5395 


1.0095 


191 


379.3 


2.358 


0.4241 


352.2 


845.4 


1197.6 


761.8 


0.5405 


1.0076 


S 


300.2 


2.335 


0.4283 


353.1 


844.7 


1197.8 


761.1 


0.5416 


1.0056 


NO 


381.0 


2.312 


0.4325 


354.0 


843.9 


1197.9 


760.3 


0.5426 


1.0036 



212 



HEAT 



Tftble SI. Frop^rtlos of Bsturftted Steftm — {eanHn^^ 

CondeDaed from the Steam Tables of Marka and Dayia by perminloii of the pabUahera, 

Longmana, Green and Co. 



Abe. 


Temp., 


8p.voL, 


Density 


Heat 


Latent 


Heat 


Intonal 


Entrnnv 


lb.. 


deg. 
fahr., 


eo-ft. 
per lb., 


lb. per 
on. It., 


of the 
liquid. 


heat of 


oontent 
of steam, 


energy 
(B.t.tt!) 


^h^AAWr 


•^MT^ 


erap.. 




' 
















evap.. 


Water, 


^JTf- 


P 


t 


f" 


!/•" 


i' 


r 


i" 


I 


• 


aoo 


381.9 


2.290 


0.437 


354.9 


843.2 


1196.1 


759.5 


0.5437 


1.0019 


20S 


384.0 


2.B7 


0.447 


357.1 


841.4 


1198.5 


757.6 


0.5463 


0.9973 


210 


386.0 


2.187 


0.457 


359.2 


839.6 


1196.6 


755.8 


0.5488 


0.9928 


215 


388.0 


2.138 


0.468 


361.4 


837.9 


1199.2 


754.0 


0.5513 


0.9885 


220 


309.9 


2.091 


0.478 


363.4 


836.2 


1199.6 


752.3 


0.5538 


0.9641 


225 


391.9 


. 2.046 


0.489 


365.5 


834.4 


1199.9 


790.5 


0.5562 


0.9799 


2)0 


393.8 


2.004 


0.499 


367.5 


832.8 


1200.2 


748.8 


0.5586 


0.9758 


235 


395.6 


1.964 


0.909 


369.4 


831.1 


120O.6 


747.0 


0.5610 


0.9717 


240 


397.4 


1.924 


0.520 


371.4 


829.5 


1200.9 


745.4 


0.5633 


0.9676 


245 


399.3 


1.887 


0.530 


373.3 


827.9 


1201.2 


743.7 


0.5655 


0.9638 


290 


401.1 


1.890 


0.541 


375.2 


826.3 


1201.5 


742.0 


0.5676 


0.9600 


260 


404.5 


1.782 


0.961 


378.9 


823.1 


1202.1 


736.9 


0.5719 


0.9525 


270 


407.9 
411.2 


1.718 


0.582 


382.5 


820.1 


1202.6 


735.8 


0.5760 


0.9454 


280 


1.658 


0.603 


386.0 


817.1 


1203.1 


732.7 


0.5800 


0.9385 


290 


414.4 


1.602 


0.624 


389.4 


814.2 


1203.6 


729.7 


0.5840 


0.9316 


aoo 


417.5 


1.551 


0.M5 


392.7 


811.3 


1204.1 


726.8 


0.5878 


0.9251 


350 


431.9 


1.334 


0.750 


406.2 


797.8 


1206.1 


713.3 


0.6053 


0.8949 


400 


444.8 


1.17 


0.86 


422.0 


786.0 


1208.0 


701.0 


0.621 


0.868 


490 


496.5 


1.04 


0.96 


435.0 


774.0 


1209.0 


690.0 


0.635 


0.844 


900 


467.3 


0.93 


1.06 


448.0 


762.0 


1210.0 


678.0 


0.648 


0.822 


660 


466.6 


0.76 


1.32 


469.0 


741.0 


1210.0 


658.0 


0.670 


0.783 



The relation between pressure and temperature is satisfactorily 
represented by Marks's equation 

logp - 10.516354 - (4873.71 /T) - 0.004050067 + 0.000001302064T*. 

For the heat oontent i" of saturated steam Davia has deduced the 
equation 

*" - 1150.3 + 0.3745« - 212) - 0.00055(f - 212) «. 

This applies to the ranise 212 des. to 400 deg. fahr. 
The heat content i' of water between SS deg. and SIS 6%g, fahr. i» 

deduoed from the experiments of Barnes and Dieterici, and above 212 deg. 
from the experiments of Dieterici and Regnault. With these fundamental 
data the remaining properties are readily calculated. For an exhaustive 
discussion of sources and methods see Marks and Davis, "Steam Tables and 
Diagrams," pp. 87-106. For density and specific heat of water at saturation 
pressures see .Table 4. 

For condenser calculations a more detailed table of the properties of 
saturated steam at temperatures from 50 deg. to 130 deg. fahr. is given in 
Table 32, which is calculated from the Marks and Davis tables. Vacuums 
are stated with reference to a 30-in. barometer; the standard atmosphere is 
equal to 30 in. of mercury when the mercury is at 58.4 deg. fahr. Absolute 
pressures are given in lb. per sq. in. and also in in. of mercury at 32 deg. fahr. 

Propertlct of Superheated Steam. An experimental basis for the 
properties of superheated steam is furnished by the researches carried on in 
the Munich laboratory. Volume measurements liave been given by Kno> 
blauoh, linde, and Klebe; specifio-heat measurements by Knoblauch and 



8UPBRHBATED STEAM 



213 



Jakob and by KnoUsuoh and Mollier. These two aeta of meamirementa 
oonnected by the ClauaiuB thermodynamio relation 

{%)r--^''ft- <^'>-'««> 
Tabto tt. StMon Tabl« lor Um tn Condaiuwr OaleuUtioni 

(Caleolated from the Steam Tablea of Marka and Davis) 



1* 




Pressure, lb. per 
sq. in. absolute 


Jia 

•gk« . 

lip 


Spesiflc volume, 
en. ft. per lb. 


Heat of the 
liquid 


Total heat of 
the steam 


Internal energy 
of evaporation 


Entropy of water 


'8 

1 


f 




P 




»' 


%' 


t' 


I 


• 


f' 


50 


29.637 


0.1780 


0.363 


1702.0 


18.08 


1081.4 


1007.3 


0.0361 


2.1226 


52 


29.(09 


0.1917 


0.390 


1586.0 


20.08 


1062.3 


1006.0- 


0.0401 


2.1164 


54 


29.579 


0.2863 


0.420 


1480.0 


22.08 


1083.2 


1004.6 


0.0440 


2.1100 


56 


29.547 


0.2219 


0.452 


1381.0 


24.08 


1084.1 


1003.3 


0.0478 


2.1037 


5ft 


29.513 


0.S65 


0.486 


1291.0 


26.08 


1085.0 


1002.0 


0.QS17 


2.0975 


P 


29.477 


0.2562 


0.522 


1288.0 


28.08 


1065.9 


1000.7 


0.0555 


2.0913 


tt 


29.439 


0.2749 


0.560 


1130.0 


30.08 


1086.8 


999.3 


0.0S93 


2.0851 


64 


29.398 


0.2949 


0.601 


1058.0 


32.07 


1067.6 


998.0 


0.0631 


2.0791 


66 


29.354 


0.3161 


0.644 


991.0 


34.07 


1088.5 


996.7 


0.0669 


2.0731 


6B 


29.308 


0.3386 


0.690 


928.0 


36.07 


1089.4 


995.4 


0.0707 


2.06n 


n 


29.259 


0.3626 


0.739 


871.0 


38.06 


1090.3 


994.0 


0.0745 


2.0613 


n 


29.208 


0.3880 


0.790 


817.0 


40.05 


1091.2 


992.7 


0.0783 


2.0556 


74 


29.153 


0.4148 


0.845 


767.0 


42.05 


1092.1 


991.4 


0.0621 


2.0499 


76 


29.095 


0.4432 


0.903 


720.0 


44.04 


1093.0 


990.1 


0.0858 


2.0443 


78 


29.034 


0.4735 


0.964 


677.0 


46.04 


1093.9 


988.7 


0.0095 


2.0386 


80 


28.968 


0.505 


1.029 ' 


636.8 


48.03 


1094.8 


967.4 


0.0932 


2.0330 


82 


28.899 


0.539 


1.098 


598.7 


50.03 


1095.6 


966.1 


0.0969 


2.0275 


84 


28.826 


0.575 


1.171 


562.9 


52.02 


1096.5 


984.8 


0.1005 


2.0220 


86 


28.749 


0.613 


1.248 


-529.5 


54.01 


1097.4 


983.4 


0.1041 


2.0165 


88 


28.646- 


0.654 


1.331 


498.4 


56.01 


1098.3 


982.1 


0.1078 


2.0112 


90 


28.580 


0.M6 


1.417 


469.3 


58.00 


1099.2 


980.8 


0.1114 


2.0058 


n 


28.489 


0.741 


1.506 


442.2 


60.00 


1100.1 


979.4 


0.1151 


2.0007 


94 


28.392 


0.789 


1.605 


417.0 


61.99 


IIOI.O 


978.1 


0.1187 


1.9954 


96 


28.290 


0.838 


1.706 


393.4 


63.98 


1101.8 


976.8 


0.1223 


1.9903 


98 


28.183 


0.891 


1.813 


371.4 


65.98 


1102.8 


975.5 


0.1259 


1.9851 


too 


28.090 


0.946 


1.926 


350.8 


67.97 


1103.6 


974.1 


0.1295 


1.9800 


MB 


27.951 


1.005 


2.045 


331.5 


69.96 


1104.5 


972.8 


0.1330 


1.9750 


104 


27.825 


1.066 


2.171 


313.3 


71.96 


1105.3 


971.5 


0.1365 


1.970O 


106 


27.692 


1.131 


2.303 


296.4 


73.95 


1106.2 


970.1 


0.1401 


1.9651 


108 


27.550 


1.199 


2.4« 


280.5 


75.95 


1107.1 


968.8 


0.1436 


1.9602 


110 


27.484 


1.271 


2.589 


265.5 


77.94 


1108.0 


967.5 


0.1471 


1.9553 


112 


27.250 


1.346 


2.740 


251.4 


79.93 


1108.8 


966.2 


0.1506 


1.9506 


114 


27.088 


1.426 


2.904 


238.2 


81.93 


1109.7 


964.8 


0.1541 


1.9458 


tl6 


26.919 


1.509 


3.073 


225.6 


83.92 


1110.6 


963.5 


0.1576 


1.9412 


118 


26.7)9 


1.597 


3.252 


214.1 


85.92 


1111.5 


962^2 


0.1611 


1.9366 


lao 


26.553 


1.609 


3.438 


203.1 


87.91 


1112.3 


960.8 


0.1645 


1.9319 


122 


26.355 


1.785 


3.635 


192.8 


89.91 


1113.2 


959.5 


0.1679 


1.9273 


124 


26.149 


1.886 


3.841 


183.1 


91.90 


1114.1 


958.2 


0.1713 


1.9228 


126 


25.931 


1.992 


4.057 


173.9 


93.90 


1115.0 


956.8 


0.1747 


1.9183 


IS 


25.706 


2.109 


4.282 


165.3 


95.89 


1115.8 


955.5 


0.1781 


1.9139 



130 



I 



25.48 



2.219 



4.52 



157.1 97.89 1116.7 954.1 0.1816 1.9095 



";"• 'ULSr 



Total-he: :-Entropr I>i*VUi 



MOLLIBH DTAaSAJU FOR STEAU 



i 

i 

(Uolliar Diagram) for Bteam. 



216 



HEAT 



Goodenough {BvUeHn No. 75, Eagr. Exper. Station, Univ. of III.) giv«e the 
following equations for volume and specific heat, which satisfy this relation 
and at the same time represent accurately the results of the experiments: 

»- 0.017 - 0.69466 (T/p) - (1 + 0.0618p^ (m/r<). logm - 10.82600. 

Op - 0.320 +0.0001267' + (23,583/r«) +p(l +a0342p^ (C'/T**), 
where p » lb. per sq. in. Also 

% « 0.3207* + 0.000063r« - (23.583/7) - p(l + 0.0342p^ {C'/T^ + 948.7. 

« - 0.2099T + 0.000063r« - (23,583/7*) ^ 

- p(l + 0.02992P *> {C'*'/T*) -f 94ar. 

« - 0.73688 log T + 0.0001 267* - (11.792/r*) ^ 

- 0.264 log p - ((7ivp/r») (1 + 0.0342P *0 - 0.0809. 
log C - 11.39361; log C" - 10.79165; log C" = log C»v . 10.69464. 

The quotient Jc^fit — <•) gives the mean q;>««iflo heat of luper- 

u 

heated gtesni between the saturation temperature U and any chosen higher 
temperature. Table 33 gives valuer of Cpm thus calculated for various 
pressures and sui>erheats. 

Table 83. Mean BpecifiG Heat of Superheated Steam 



Prasflure, lb. por 


Superhestt deg. fahr. 


«q. in. 





50 


100 


200 


300 


400 


500 


600 


I 


0.476 


0.471 


0.466 


0.462 


0.461 


0.460 


0.462 


0.465 


2 


0.474 


0.470 


0.465 


0.461 


0.460 


0.459 


0.461 


0.464 


3 


0.475 


0.470 


0.465 


0.461 


0.460 


0.461 


0.462 


0.465 


5 


0.477 


0.472 


0.467 


0.463 


0.461 


0.462 


0.464 


0.467 


10 


0.483 


0.477 


0.471 


0.467 


0.465 


0.466 


0.466 


0.470 


15 


0.490 


0.483 


0.476 


0.471 


0.469 


0.470 


0.471 


0.474 


20 . 


0.496 


0.488 


0.480 


0.475 


0.473 


0.473 


0.475 


0.477 


25 


0.500 


0.493 


0.486 


0.480 


0.477 


0.477 


0.470 


0.480 


30 


0.506 


0.498 


0.490 


0.483 


0.480 


0.479 


0.481 


0.483 


40 


0.515 


0.506 


0.498 


0.490 


0.486 


0.484 


0.485 


0.487 


50 


0.524 


0.515 


0.506 


0.497 


0.491 


0.489 


0.490 


0.491 


60 


0.534 


0.523 


0.513 


0.503 


0.497 


0.494 


0.494 


0.495 


W 


0.550 


0.536 


0.525 


0.512 


0.505 


0.502 


0.501 


O.SOI 


100 


0.566 


0.550 


0.538 


0.523 


0.514 


0.509 


0.507 


0.507 


125 


0.582 


0.566 


0.553 


0.535 


0.524 


0.517 


0.515 


0.514 


150 


0.600 


0.581 


0.566 


0.546 


0.533 


0.525 


0.522 


0.521 


200 


0.627 


0.606 


0.588 


0.564 


0.549 


0.540 


0.535 


0.533 


250 


0.653 


0.629 


0.609 


0.581 


0.564 


0.553 


0.547 


0.543 


300 


0.676 


0.650 


0.627 


0.597 


0.578 


0.565 


0.558 


0.553 



With the aid of the table of mean specific heats, the heat content and en- 
tropy of superheated steam may be calculated easily and with a good degree 
of approximation. Thus, 

t - t" + cpmit - «.), • - •' + cp« log. (T/r.), 

where i" and t" [^s* + (^/70] A^e saturation values taken from the table on 
p. 209. 

Szample. Steam at a pressure of 100 lb. per sq. in. !• superheated 240 dsg. From 
Table 33, c,. - 0.510. and from Table 81, t" - 1186.3. «" - 1.0020, f« - 327.8. 
Hence, i - 1186.3 + 0.819 X 240 - 1310.0 B.t.tt., • - 1.6020 + 0.619 log* ((54(7.8 + 
469.6)/(327.8 + 450.6)] - 1.7402. 

Table 34 gives properties of superheated steam condensed from the steam 
tables of Marks and Davis. A MoUier diagram for steam is given on pp. 
214 and 215. 



SUPBRBBATED STB AM 



217 



TMito M. FroptrilM of lup«rli«at«d Btaam 

(OondeoMd from Marks and Davis's ' Iteam Tables axul Diagrams'*) 
f M Spedfio volume in cu. ft. per lb.; t »■ Total heat in B.t.u. per lb.; 

a — Entro:''v 



lb. iwr 



Temp, of 
■ainrated 



dig. fahr. 



Superheat, deg. fahr. 



20 



60 



100 



ISO 



200 



250 



300 



228UI 
2fi7.3 

2nj 

3t2UI 
S2I^ 
3413 
3S3.I 
363.6 
373.1 
381.9 



K9 
397.4 
404.5 
411.2 
417.5 



20.73 
1165.7 
1.7456 

10.83 
1179.3 
I .6893 

7.40 
1187.3 
1.6568 

5.65 
1193.0 
1.6338 

4.58 

1197.5 
1.6160 

3.85 
1201.1 
1.6016 

3.32 
1204.3 
1.5894 

2.93 
1207.0 
1.5789 

2.62 
1209^ 
1.5M7 

2.37 
1211.6 
1.5614 

2.16 
1213.6 
1.5541 

1.99 
1215.4 
1.5476 

1.84 
1217.1 
1.5416 

1.72 
1218.7 
1.5362 

1.60 
1220.2 
1.5310 



21.37 
1175.2 
1.7587 

11.16 
1189.1 
1.7025 

7.63 
1197.5 
1.6696 

5.83 
1203.6 
1.6469 

4.72 
1208.4 
1.6294 

3.98 
1212.4 
1.6152 

3.44 
1215.8 
1.6031 

3.03 
1218.8 
1.5928 

2.71 
1221.5 
1.5838 

2.45 
1223.9 
1.5757 

2.24 
1226.2 
1.5686 

2.06 
1228.3 
1.5623 

1.91 

iao.3 

1.5564 

1.78 
102.2 
1 .5512 

1.66 
1234.1 
1.5462 



22^01 
1184.6 
1.7716 

11.50 
1196.9 
IJ151 

7.86 
1207.7 
1.6823 

6.00 
1214.0 
1.6594 

4.86 
1219.1 
1.6420 

4.10 
1223.3 
1.6279 

3.54 
1226.8 
1.6159 

3.12 
1Z30.0 
1.6056 

2.80 
1232.8 
1.5767 

2.53 
1235.5 
1.5886 

2.31 
1237.9 
1.5816 

2.13 
1240.1 
1.5753 



1.84 
1244.3 
1.5643 

1.72 
1246.2 
1.5594 



22.63 
1194.1 
1.7840 

11.82 
1208.7 
1.7273 

8.06 
1217.7 
1.6944 

6.18 
1224.2 
1.6716 

5.00 
1229.5 
1.6541 

4.22 
1233.8 
1.6400 

3.65 
1237.5 
1.6280 

3.21 
1240.8 
1.6177 

2.88 
1243.8 
1.6068 

2.61 
1246.5 
1.6007 

2.38 
12481 
1.5936 

2.20 
1251.3 
1.5873 



1.97 2.04 2.10 
1242.31253.41264.1 
lJ6f951J615 1.5926 






1.90 
1255.5 
1.5762 

1.78 

l!5713 



23.25 
1203.5 
1.7%1 

12.13 
1218.4 
1.7392 

8.30 
1227.6 
1.7062 

6.34 
1234.3 
1.6833 

5.14 
1239.7 
1.6658 

4.33 
1244.1 
1.6517 

3.75 
1248.0 
1.6395 

3.30 
1251.3 



1.6292 1.6561 



2.96 
1254.3 
1.6201 

2.68 

1257.1 
1612.0 

2.45 
1259.6 
1.6049 

2.26 
1261.9 
1.5965 



1.95 
1216.2 
IJ873 

1.83 
1268.2 
1.5824 



24.80 
1227.1 
1.8251 

12.93 
1242.4 
1.7674 

8.84 
1252.1 
1.7342 

6.75 
1259.0 
1.7110 

5.47 
1264.7 
1.6933 

4.62 
1269.3 
1.6789 

4.00 
1273.3 
1.6666 

3.53 
1276.8 



3.16 
1279.9 
1.6468 

2.86 
1282.6 
1.6385 

2.62 
1285.2 
1.6312 

2.42 
12B7.6 
1.6246 

2.24 
1289.9 
1.6186 

2.09 
1291.9 
1.6133 

1.96 
1294.0 
1.6062 



26.33 
1250.6 
1.8524 

13.70 
12G6.4 
1.7940 

9.36 
1276.4 
1.7603 

7.17 
1283.6 
1.7368 

5.80 
1289.4 
1.7188 

4.89 
1294.1 
1.7041 

4.24 
1296.2 
1.6916 

3.74 
1301.7 
1.6810 

3.35 
1304.8 
1.6716 



27.85 
1274.1 
1.8781 

14.48 
1290.3 
1.8189 

9.89 
1300.4 
1.7849 

7.56 
1307.8 
1.7612 

6.12 
1313.6 
1.7428 

5.17 
1318.4 
1.7280 

4.48 
1322.6 
.1.7152 

3.96 
1326.2 
1.7043 

3.54 
1329.5 
1.6948 



29.37 

1297.6 
1.9026 

15.25 
1314.1 
1.8427 

10.41 
1324.3 
1.8081 

7.95 

1331.9 

1.: 



3.04 3.21 
1307.7 1332.4 



1.6632 

2.78 
1310.3 
1.6558 

2.57 
1312.8 
1.6492 

2.39 
13M.1 
1.6430 

2.22 
1317.2 
1.6575 

2.09 
1319.3 
1.6323 



^.44 
1337.8 
1.7656 

5.44 

1342.7 
1.7505 

4.71 
1346.9 
1.7376 

4.15 
1350.6 
1.7266 

3.n 

1353.9 
1.7169 

3.36 

1357.0 
1.7062 

3.10 
1359.6 
1.7005 

2.85 

1362.3 
1.6937 

2.65 
1364.7 
1 .665811.6874 



1.6862 

2.^ 
1335.1 
1.6787 

2.71 
1337.6 
1^6720 

2.52 
1340.0 



2.35 
I3«.2 
1.6103 

2.21 
1344.3 
1.6550 



2.46 
1367.0 
1.6616 

2.33 
1369.2 
1.6765 



218 



HBAT 



Ammonia Vapor. The tables of Goodenoush and Mosher {BvUelin No. 
66, Engineeriiig Ezper. Station, University of Illinois), represent the latest and 
probably the most accurate values of the thermal properties of saturated vapor 
of ammonia. See Table 35. 

Table S6. Propartiei of Ammonia 



Temp., 
deg. 

fahr 
I 



-40 
-35 
-30 
-25 

-20 
-15 
-10 
- 5 


5 

10 
15 

• 

20 
25 
30 
35 

40 
45 
50 
55 

60 
65 
70 
75 

80 
85 
90 
95 

too 

105 
110 
115 

120 
125 



Pressure t 

lb. per 

s<l. m.. 

abs. 



Specifio volume 



of Uqoid. 
ou. ft. 
per lb. 



of sat. 
vapor, cu. 
ft. per Ib« 



Heat ooatent 



of 

liquid 



of sat. 
vapor 



.*'/ 



Heat 

of 
vapor- 
isation 



Inters 

nal 
energy 

of 
vapor- 
isation 
I 



Entropy 



of o' 

r/T 



tO.I2 
11.74 
13.56 
15.61 


0.0234 
0.0235 
0.0236 
0.0238 


17.91 
20.46 
23.30 
26.46 


00239 
0.0240 
0.0241 
0.0242 


29.95 
33.79 
38.02 
42.67 


0.0244 
0.0245 
0.0246 
0.0248 


47.75 
53.30 
59.35 
65.91 


0.0249 
0.0250 
0.0252 
0.0253 


73.03 
80.75 
89.09 
96.03 


0.0255 
0.0256 
0.0258 
0.0259 


107.7 
118.1 
129.2 
141.1 


0.0261 
0.0263 
0.0264 
0.0266 


153.9 
167.4 
181.8 
197.3 


0.0268 
0.0270 
0.0271 
0.0273 


213.8 
231.2 
249.6 
269.7 


0.0275 
0.0277 
0.0280 
0.0282 


289.9 
311.6 


0.0284 
0.0286 



25.45 
22.14 
19.35 
16.95 

14.89 
13.15 
11.63 
10.32 

9.19 
8.20 
7.34 
6.583 

5.920 
5.336 
4.820 
4.364 

3.959 
3.599 
3.278 
2.992 

2.734 
2.503 
2.296 
2.109 

1.940 
1.788 
1.650 
1.524 

1.408 
1.305 
1.210 
1.122 

1.042 
0.970 



-75.3 
-70.2 
-65.0 
-59.8 

-54.6 
-49.4 
-44.2 
-38.9 

-33.7 
-28.4 
-23.2 
-17.9 

-12.6 

- 7.3 

- 1.9 
+ 3.5 

8.9 
14.3 
19.8 
25.3 



30.9 
36.5 
42.1 
47.8 



53.6 
59.4 
65.3 
71.3 



526.6 
528.2 
529.8 
531.3 

532.8 
534.3 
535.7 
537.1 

538.5 
539.9 
541.2 
542.5 

543.7 
545.0 
546.2 
547.4 

548.5 
549.7 
550.8 
551.9 

552.9 
554.0 
555.0 
556.0 

557.0 
557,9 
558.9 
559.8 



77.3 560.7 

83.4| 561.6 

89.6' 562.5 

95.9 563.3 



102 
108 



564.2 
565.0 



601.9 
598.3 
594.7 
591.1 

567.4 
583.6 
579.9 
576.1 

572.2 
568.3 

564.4 
560.4 

556.3 
552.2 
546.1 
543.9 

539.7 
535.3 
531.0 
526.5 

522.0 
517.5 
512.8 
506.1 

503.4 
498.5 
493.5 
488.5 

483.4 
478.2 
472.9 
467.4 

461.9 
456.3 



I 



554.2 
550.2 
546.2 
542.1 

538.0 
533.9 
529.8 
525.6 

521.4 
517.1 
512.9 
508.6 

504.2 
499.8 
495.4 
491.0 

486.5 
481.9 
477.3 
472.7 

468.0 
463.3 
458.5 
453.7 

448.8 
443.9 
438.9 
433.9 

428.7 
423.5 
418.3 
412.9 

407 5 
402.0 



0.1653 
0.1531 
0.1410 
0.1290 



-0 
-0 



1171 
1054 
-0.0938 
-0.0824 



-0.0709 
-0.0595 
-0.0483 
-0.0372 




0.0173 
0.0280 
0.0387 
0.0494 

0.0601 
0.0708 
0.0813 
0.0919 

0.1025 
0.1132 
0.1238 
0.1344 

0.1450 
0.1557 
0.1664 
0.1772 



1881 
1990 



1.4343 
1.4090 
1.3842 
1.3598 

1.3360 
1.3126 
1.2896 
1.2671 

1.2449 
1.2231 
1.2017 
1.1806 



.1599 
.1395 
.1194 
.0996 

.0601 
0009 
.0419 
.0231 



1.0046 
0.9663 
0.9683 
0.9504 

0.9328 
0.9153 
0. 
0. 



0.8638 
0.8469 
0.8302 
0.8135 

0.7969 
0.7805 



The relation between pressure and temperature is derived from the vapor- 
pressure law, using as a basis the Marks equation (p. 212) connecting the pres- 
sure and temperature of saturated steam. For a given pressure p, let T^ 
denote the saturation temperature (absolute) of water vapor and Ta the corre- 
sponding temperature of ammonia vapor. Then 

Ta - 1/[(1.70366/T») - 0.0002242]. 
Below 160 deg. fahr. the volume r' of liquid ammonia is given by 

!»' - 0.06335 - 0.016 log (273.2 - /). 



AMMONIA— SULPHUR DIOXIDE 219 

The diSeronce >" — ■' ig found from theCUi>eyToarelktioii(p.208),sDdfroni 
this a", the npeeific volume of the uturftted vapor, is dclemuucd. TheI»taDt 
heat ie cslculated from the empirical formula 

log r = 1.856064 + 0.37 log (273.2 - t). 
SupftfliaMad iLiiunanift. The speciGc volume of superheatad uamoDia 
isgiveD by the oharacteriatic equation of MoBher, via.: - 

» + aiO -0.6321 {T/p) - (79,433 X lO'/T*). 
The apecific heat at cooatant presaure ia given by the empirical formula 

e, - 0.382 + 0.0001747" + {Cp/T*). log C - 13.044706. 
For the heat coutent and entropy the following formula an deduced from 
the preceding: 

1 - 0.3827" + 0.0000877"> - (Cp/T>) - 0.0185p + 368. log C - 12.945734. 
t - 0.8796 log 7" + 0.0001747" - 0.2695 l<^ p - {C"p/T*) - 0.8266. 

log C" - 12.8e«6M. 



Tolal'heat-Eiitropy Diagram (Molliet Diagram) for Ammonia. 

Table 36 gives these properties of superheated NHi for varioua preMurea 
•od degrees o( superheat. A M oilier diagram for ammonia is givenabove. In 
uaing this diagrnm it should be noted that the constsnt^^ntropy lines are 
diagonals (not vertieals), and that adiabHtJcB have tfas same slope as these 
diagooaU. 

Sulphur Dl0Sid« (BOi). The properties of saturated vapor of SOi given 
in Table 37 are baaed on the reseBiBhes of Cailletet and Matfaias. Certain of 
tbeoe properties are given by the following empirical formula: 

t'- 0.3194 + 0.000631/ -32), i =0.0113. 

»' - 0.00065(( - 32). r/T - 0.3327 - 0.00129(i - 33). 



220 



HEAT 



I 



Table S6. Prop«rttoi of BuperbMktod iLmmoiiift 

(Condeiued from the Tables of Qoodenough and Moaher) 
• - Specific volume in cubic feet per pound: i - Total heat in B.t.tt. per pound; 

tt WB Entropy 



Preflaure, 

lb. per 

sq. in. 

Abe. 



20 



40 



50 



80 



100 



120 



140 



IM 



180 



200 



250 



300 



Temp, of 
saturated 
▼apor. 
deg.fahr. 



-15.9 



12.2 



90.5 



44.5 



56.0 



65.8 



74.5 



82.3 



89.4 



95.9 



1 10. 1 



122.4 



Superheat, dec. ffthr. 



20 



40 



60 



80 



100 



ISO 



200 250 



300 



14. 
545. 
1.2339 



7.40 

553.9 

1.1742 

5.04 

559.1 

1.1396 

3.84 
562.8 



14.9 

556.1 

1.2569 

7.76 

.565.5 

1.1974 

5.30 

571.2 

1.1629 

4.04 
574.3 



15.6 

566.7 

1.2784 

8.12 

576.8 

1.2188 

5.54 

582.9 

1.1846 

4.22 
587.4 



1.1154 1.1389 1.1606 



3.10 3.26 
565.7 578.6 
1.0968 1.1204 



3.41 

590.9 

1.1422 



2.61 2.74 2.87 
I 568.2 581.4, 593.9 
1.0818 1.1055 1.1274 



2.251 2.37 

570.2! 583.6 

1.0693 1.0931 



1.96 

572.0 

1.0585 

1.77 

573.6 

1.0491 

1.59 

575.0 

1.0407 

1.28 

578.0 

1.0232 



2.06 

589.7 

1.0824 

1.86 

587.5 

1.0731 

1.67 

589 1 

1.0648 

1.35 
592.4 



2.48 
596.4 



16.3 

577.1 

1.2986 

8.46 

587.7 

1.2390 

5.77 

594.2 

1.2047 

4.40 

599.0 

1.1808 

3.56 

602.8 

1.1625 

2.99 
6059 



16.9 

587.4 

1.3178 

8.80 

598.3 

1.2581 

6.01 

605.2 

1.2238 

4.57 

610.3 

1.1999 

3.70 

614.3 

1.1815 

3.11 
617.6 



18.6 

612.7 

1.3625 



20.2 

638.0 

1.4033 



9.64 ! 10.46 

624.6 650.6 

1.3021 1.3422 



1.1477 1.1667 



2.58 
608.7 



269 
620.6 



1.1150 1.1354 1.1544 



6.57 

632.1 

1.2676 



7.12 

658.6 

1.3074 



5.00 5.42 

637.7 664.6 

1.243611.2830 

4.05' 4.38 

642.21 669.4 

1.2251 1.2645 



2.18 

598.6 

1.1043 

1.94 

600.6 

1.0950 

1.75 

602.4 

1.0668 

1.41 
606 1 



1 .0474 1 .0695 



1 07 1.13 1 18 

580 5< 595.3 609.3 

I. Q093!l.(B35 1.0556 



2.27 

611.1 

1.1247 

2.03 

613 2 

I. 1154 

1.83 

615.2 

1.1072 

1.47 

619.3 

1.0899 

1.23 

622.7 

1.0761 



2.36, 

623.2 

1.1438 

2.11 

625.4 

1.1346 

1.90 

627.5 

1.1263 

1.53 

631.9 

1.1090 

1.28 

635.5 

1.0953 



3.40 

646.0 

1.2103 

2.94 

649.3 

1.1979 

2.58 

652.1 

1.1872 

2.31 

654.7 

1.1779 

2.08 

657.0 

1.1697 

1.68 
661.9 

1.1524 

1.41 

666 1 

1.1386 



3.68 

673.4 

1.2494 

3.17 

676.9 

1.2370 

2.79 

680 1 

1.2263 



2! 8 
663.4 



23.4 
689.1 



1.4413 1.4771 



11.26 
676.6 



12.07 
7027 



1.3795 1.4145 



7.66 

684.9 

1.3442 

5.83 

691.2 

1.3196 



8.20 

711.3. 

1.3787 

6.23 

717.9 

1.3538 



4.71 5.03 
696.3 723.2 
1.3008 1.3348 



3.96 

7006 

1.2856 

3.41 

704.3 

1.2730 



4.23 

727.6 

1.3195 

3.65 

731.5 

1.3067 



3.00' 3.21 

707.6 735.0 

1.26221.2957 



2.49 2.68 2.86 
682.81 710.51 738.1 
1.2168 1.252711.2861 



2.25 

685.4 

1.2065 

1.81 

6908 

1.1911 

1.52 

695.4 

1.1772 



2.411 2.57 

713.3 741.0 

1.2442.1.2776 



1.95 
719.0 



2.06 
7470 



1 .2266 1 .2598 

1.63* 1.74 

723 9; 752.1 

1 .2125' 1. 2455 



Carbon Diozido (COs). The properties of CO« vapor have been investi- 
gated experimentally by Amagat. The results are given in Table 38. The 
following are the empirical formula devised by MoUier: 

Critical temperature, Tk -> 547.83 deg. fahr*. absolute, 
p = 42.2066 KT/ISO) - 11*»» r - 0.68167^ "(r* - T)^'^ 
& - 0.000185r + 0.285 {r/T) + 0.215 r/(T» - T) 
e - 0.10155 + 0.000185(f - 32) - r/2r 



PROPERTIES OF SULPHUR DIOXIDE 



221 



Table 87. Propertiei of Sulphur Dioiide 



Temp., 

dec. 

fakr. 

f 



lb. per 

eq. in. 

P 



Spedfio 
volume of 
■at. vapor 
V 



Heat content 



of 
liquid 



of 
vapor 



Heat 

of 
vapor- 
isation 

r 



Internal 

energy of 

vapor- 

iiation 

I 



Bntropy 

of 

liquid 

• 



En- 
tropy of 
vapor- 
isation 

r/T 



-25 
'20 
-15 
-10 
- 5 


5.02 
5.92 
6.86 
7.90 
9.03 


16.250 

12.980 

10.910 

9.510 

8.410 


-17.14 
-15.69 
-14.28 
-12.85 
-11.39 


159.32 
159.94 
160.52 
161.02 
161.50 


176.46 
175.63 
174.80 
173.87 
172.89 


163.10 
162.04 
161.04 
160.00 

158.90 


-0.0368 
-0.0338 
-0.0308 
-0.0274 
-0.0240 


0.4057 
0.3996 
0.3935 
0.3869 
0.3803 



5 

10 

15 


10.35 
11.80 
13.40 
15.15 


7.490 
6.660 
5.910 
5.210 


- 9.907 

- 8.388 

- 6.842 

- 5.321 


161.92 
162.29 
162.59 
162.87 


171.83 
170.68 
169.43 
168.19 


157.70 
156^43 
154.95 
153.59 


—0.0208 
-0.0176 
-0.0141 
-0.0110 


0.3739 
0.3675 
0.3606 
0.3546 


20 

25 

*30 

35 


17.09 
19.17 
21.46 
24.04 


4.635 
4.135 
3.716 
3.350 


- 3.780 

- 2.212 

- 0.622 
0.968 


163.12 
163.30 
163.43 
163.51 


166.90 
165.51 
164.05 
162.54 


152.26 
150.84 
149.36 
147.75 


—0.0079 

-0.0046 

-0.0012 

0.0020 


0.3483 
0.3418 
0.3351 
0.3287 


40 
45 
SO 
55 


26.82 
29.90 
33.38 
36.96 


3.005 
2.700 
2.433 
2.210 


2.565 
4.156 
5.850 
7.510 


163.55 
163.53 
163.45 
163.33 


160.99 
159.37 
157.60 
155.82 


146.11 
144.40 
142.68 
140.92 


0.0051 
0.0063 
0.0117 
0.0150 


0.3224 
0.3160 
0.3094 
0.3029 


60 
65 
70 
75 


40.53 
44.92 
49.S6 
54.33 


2.00) 
1.817 
1.650 
1.499 


9.203 
10.900 
12.580 
14.310 


163.19 
162.99 
162.73 
162.44 


153.99 
152.09 
150.15 
148.13 


138.95 
137.12 
135.29 
133.28 


0.0182 
0.0215 
0.0248 
0.0280 


0.2965 
0.2900 
0.2835 
0.2771 


80 
85 
90 
95 


59.58 
65.25 
71.25 
77.66 


1.362 
1.238 
1.137 
1.041 


16.090 
17.830 
19.640 
21.420 


162.09 
161.70 
161.25 
160.74 


146.00 
143.87 
141.61 
139.32 


131.16 
129.04 
126.85 
124.63 


0.0312 
0.0345 
0.0377 
0.0410 


0.2707 
0.2642 
0.2578 
0.2513 


100 
105 


9! 18 


0.950 
0.867 


23.170 
24.960 


160.19 
159.60 


137.02 
134.64 


122.39 
120.02 


0.0443 
0.0475 


0.2442 
0.2380 



Propoitioo of Other BefHfforattng Fluids. In addition to the three 
fiiiids whoee properties have been given in the preceding tables, the following 
fluids have been used to some extent: 

Ethyl chloride (CtHsCl); methyl chloride (CH|C1); nitrous oxide (NiO) 
and Biotet^s fluid, a inixture of SOt and COi in the proportion of 64 parts SOt 
to 44 parts COs by weight. 

The vapor preMurot of these fluids are given in Table 39. The other ther- 
mal properties are not at present well known and the values here given must 
be regarded as rude approximations. Nitrous oxide closely resembles car- 
bon dioxide in its behavior: the vapor pressure and the density of the two 
fluids are nearly identical. . 

The latent heat of ethyl chloride is given as 174.5 B.t.u., and that of 
methyl chloride as 174 B.t.u., temperature not specified, but presuxnebly under 
atmospheric pressure. Caiiletet and Mathias give the following formula for 
the latent heat of NtO: r* - 237.15 (97.5 - - 0.028(97.5 - f)>. 

From this formula the foUowing values are found: 

fori- -20 20 40 60 80 dag. fahr. 

r-i 122.7 120.4 118.2 102.8 87.1 62.2 

The gpooillo hoat of NiO vapor at constant pressure is 0.225. The spedfie 
heat of the vapor of ethyl chloride is given by Regnault as 0.274 between 06 
d^. and 340 deg.; the specific heat of the liquid is 0.4276 between —18 
deg. and 40 deg. > 

The density of NtO may be taken the same as that of COi. According to 
Begnanlt, the density of ethyl chloride gas is 2.2268 times the density of for. 



222 



HEAT 



Table 88* Proparttoi of Carbon Dioxide 



Temp, 
deg. 
fahr. 

i 



PresBure, 
lb. ]^er 
sq. in. 



Spedfio volume 



1 Heat content 



Entropy 



of liquid, 
ou. ft. 
per lb. 

• 



<A rapor, 
ou. ft. 
per lb. 




-25 
-20 
-15 
-10 
' 5 



5 
10 
15 

20 
25 
30 
35 

¥i 
45 
50 
55 

60 
65 
70 
75 

80 
85 
87 
88.4: 



a 



203.4 
221.0 
240.5 
261.8 
284.1 

308.0 
334.2 
362.5 
391.0 

421.6 
454.7 
488.8 
525.5 

564.5 
606.0 
650.0 
696.0 

744.0 
794.0 
847.0 
906.0 

965.0 
1026.0 
1052.0 
1071.0 



0.01551 
0.01556 
0.01565 
0.01578 
0.01594 

0.01612 
0.01631 
0.01652 
0.01675 

0.0I6S6 
0.01720 
01747 
0.01776 

0.01805 
0.01835 
0.01870 
0.01918 

001986 
0.02052 
0.02136 
0.02230 

0.02365 
0.02620 
0.02782 
0.0346 



0.4575 
0.4173 
0.3810 
0.3481 
0.3185 

0.2918 
0.2672 
0.2450 
0.2244 

0.2060 
0.1882 
0.1724 
0.1580 

0.1444 
0.1323 
0.1205 
0.1090 

0.0986 
0.0890 
0.0816 
0.0706 

0.0614 
00500 
0440 
0.0346 



26.91 
24.75 
22.72 
20.56 

-18.31 



100.22 
100.50 
100.74 
100.88 
100.99 



127.13 
125.25 
123.46 
121.44 
119.30 



110.8 
109.0 
107.3 
105.4 
103.4 



-0.0561 
-0.0513 
-0.0467 
-0.0419 
-0.0372 



0.2925 
0.2851 
0.2778 
0.2702 
0.2626 



16.00 101.00 

13.73 100.97 

11.36 100.89 

8.94 100.70 



117.00 101.3 

114.70 99.2 

112.35 96.9 

109.64 94.3 



-0.0325 0.2549 

-0.0276 0.2470 

-0.0227 0.2391 

-0.0176 0.2309 



- 6.40 100.43 106.83 

- 3.74 100.08 102.82 

- 1.04 99.43 100.47 
+ 1.74 99.00 97.26 

4.36 96.25 93.89 

7.54 97.32 89.78 

10.76 96.30 85.54 

14.18 95.00 80.62 

17.85 93: 54 75.69 

21.50 91.67 70.17 

26.02 89.35 63.33 

30.96 86.36 55.40 

36.80 82.80 46.00 

44.67 76.60 30.23 

48.98 71.80 23.82 

61.45 61.45 0.00 



91.8 -0.0126 0.2228 

88.4 -0 0074 0.2143 

86.7 -0.0021 0.2014 
83.6 -f 0.0032 0.1968 

80 4 0.0087 0.1876 

77.05 0.0145 1780 
73.31 0.0205 0.1679 
69.16 0.0268 0.1572 

64.90 0.0334 0.1461 

60.08 0.0406 1334 
54.03 0.0483 0.1201 
47.20 0.0576 0.1037 

39.16 0.0684 0.0843 

26.80 0.0628 0.0559 

18.25 0923 0.0393 

0.00 0.1120 O.OOO 



Table 39. Vapor Preeeures of Refrigerating Fluids (Lb. per 8q. In.) 



Temp., 
deg. 
fahr. 



Ethyl 
chlor- 
ide 
CiH»Cl 



Methyl xru,^.,o Pictct'fl 

ide , 'SiJf 6480,+ 
CHiCl ""^ 44COi 






fahr. 



ide 
CtHiCl 



Methyl 
chlor- 
ide 
»CH.C1 



-20 


2.26 


-15 


2.64 


-10 


3.03 


- 5 


3.50 





4.04 


5 


4.65 


10 


5.31 


15 


6.02 


20 


6.79 


25 


7.63 


30 


8.58 


35 


9.62 



Nitrous 
oxide 
NsO 



40 
45 
50 

55 
60 
65 
70 



10.76 
12.04 
13.35 

14.73 
16.33 
18 15 
20 02 



11.73 
13.25 
14.86 
16.69 
18.73 

20.87 
23.24 
25.86 
28.68 
31.78 

35.13 

38.83 

42.7 

47.0 

51.5 

56.4 
61.7 
67.3 
73.3 



296 

315 
336 
358 

381 
405 
431 
458 
487 

518 
550 
584 

620 
658 

698 
740 
785 
832 



11.7 
12.7 
13.5 
14.4 
15.6 

17.0 
18.6 
20.3 
22.2 
24.2 



26 
28 
31 
34 
37, 



41.0 
44.4 
47.8 
51.6 



75 
80 
85 
90 
95 

100 
105 
110 
115 
120 

125 
130 
135 
140 
145 

150 
155 
160 



22.0 
24.2 
26.6 
29.1 
31.8 



79.8 

86.7 

94.2 

102.0 

110.1 



881 

933 

988 

1046 

1107 



Piotet't 

fluid 
64SOt+ 
44 COi 

55.8 
60.1 
64.5 
69.2 
74.2 



34.7 1171 79.5 

37.8 1239 84.7 

41.1 89.6 

44.6 94.4 

48.3 98.9 

52.3 

56.5 

61.0 

65.8 

70.7 

76.1 

81.6 

87.6 



MIXTURE OF OASES AND VAPOR 



223 



Spedal Changes of Btate. Mixtures of Vapor and Liquid 

t Isothermal or Constant Pressure : t » const, p « cozuit. 
If the initial and final qualities are xi and £s, respectively, then 

Q - Mr{xt - *i). I7i - I7i - Ml{xt - «»). 

L - j}(Vt -7i) - Afp (•' - i/Hxt - xi). 

1 Constant Volume : 

xt - xi iv"i — »'i)/(«"i - ft) - xi «"i/i»"i, approz. 

Q^Ut^Vi^M [(t't + xA) - (i'l + xiZ»)l 
S. Adiabatic: 9 » const. 

•'x + {xin/Ti) = «'» + (xirj/r« ). Q - 0. 

The relation between p and v during an adiabatio change may be represented 
approximately by the equation po^  const. The exponent n is not constant, 
however, but varies with the initial quality and initial pressure, as shown by 
Table 40. 

Table 40. Values of n (Water Vapor) 



hiitial 


Initial pteasurB, lb. per aq. in. absolate 


qvdity 


20 


40 


m 


80 


100 


120 


140 


160 


180 


200 


220 


240 


1.00 
0.«5 
0.90 
0.85 
0.80 
0.75 


1.131 
1.127 
1.123 
1.119 
1.115 
I.IH 


1.132 
1.128 
1.123 
1.119 
1.115 
1.110 


1.133 
1.129 
1.124 
1.119 
1.114 
1.110 


1.134 
1.130 
1.124 
1.119 
1.114 
1.109 


1.136 
1.131 
1.125 
1.120 
1.114 
1.109 


1.137 
1.131 
1.125 
1.120 
1.114 
1.106 


1.138 
1.132 
1.126 
1.120 
1.113 
1.107 


1.139 
1.133 
1.126 
1.120 
1.113 
1.106 


1.141 
1.134 
1.127 
1.120 
I.tl3 
1.106 


1.142 
1.135 
1.127 
1.120 
1.113 
I.IOS 


1.143 
1.136 
1.128 
1.120 
1.112 
,1.104, 


1.145 
1.137 
1.129 
1.121 
1.112 
1.104 



The volume at the end of expansion (or compression) is Vi » Vi {pi/ptV^*, 
and the external work 

W - (piVi - p,F«)/(n - 1) - piVx[l - (pi/pi)^"''^'"]/(rk - 1) 
1 Constant Quality: For a change of state with the quality x constant, 
aa approximate relation between p and 9 for water vapor, is 

ppLoeii « 4g4,2 x»«»". 

For dry steam a: -» 1, and the relation becomes pO«»«V' - 327.7. 

This formula may be used for calculating approximately the volume v" ol 
aatorated steam for a given pressure p. 

Mixture of Qases and Vapors 

Voistare in the Atmosphere. Atmospheric 
air always contains a certain amount of water ' 
vapor mixed with it. The pressure of the vapor 
csimot exceed the saturation pressure correspond- 
io( to the temperature of the atmosphere. Gen^ 
^(^y. the vapor is in a superheated state, and the 
PVMBore is less than the saturation pressure. For 
A mixture of water vapor and air it may be as- 
"imed that Dalton's law holds. Thus, the pres- 
>ue ps indicated by the barometer is the sum of 
P'l the pressure of the vapor, and p", the pressure 
<rftheair. On the T-5 plane. Fig. 13, let A denote ' 
tbe state of superheated water vapor at the tem- Fig. 13. 

perature t of the atmosphere, and let m denote the weight of the vapor per 




224 HEAT 

oubio foot. Point C rapreients vapor in iho saturated eondition at the 
same temperature I. The density or weight per cubic foot is greater in 
state C than in state A. Denoting by mi the weight per cubic foot in state 
C, the ratio m/mi is the r«latiT« humidity of the air under the given oon< 
ditions. If the mixture be cooled at constant pressure, ther curve AB repre* 
sents the change of state of the vapor, and at some lower temperature lo tho 
vapor becomes saturated and upon further cooling begins to condenae. The 
temperature U is called the dew point corresponding to the state A, If 
]/^ and ]/^ denote the vapor pressures corresponding to the temperaturet 

to and i, respectively (at pointsB and C), then the relative humidity is i^proxi- 
mately the ratio j/^ /v^^. 

Prop«rtlM of Moiat Air. 

Let i •- temperature of air, deg. fahr. 

T « < + 459.6, the corresi>onding absolute temperature. 
h ■• relative humidity. 

B "■ barometric pressure, in inches of mercury, 
s  pressure of BoiuraUd vapor corresponding to temperature t, in 
inches of mercury. 
jy >- weight per cu. ft. of saturated vapor at temperature U lb. 
ly « weight per cu. ft. of dry air at temperature i and pressure B, lb. 
D ■>■ weight per cu. ft. of mixture at temperature ^ and with relative 

humidity h, lb. 
R ■• 53.34, the characteristic constant of dry air. 
Rm *" characteristic constant of mixture. 

The partial proisure of the vapor is h€, that of the b3xB — he. Hence, by 
▼oluina, the mixture has hefB parts of vapor, and {B — he)/B psrts of air; 
that LB, the addition of moisture reduces the effective volume of. air 100 he/B 
per cent. 

The constant B» of the mixture is given hyRm » 53.84/[l — 0.378(WB)]. 

The woight per eu, ft. of the mixture Is D -^ hD' + {D"{Ji - A«)/B), and 
this reduces to X> « 1.326(B/7) - OMl{he/T). 

These formuls apply only when the vapor pressure is small relative to the 
total pressure. TaUe 41 facilitates the use of the preceding equations. 

Bxaoxpls. The tempsfature of the air ia 84 deg. fahr., the relative humidity 0.70, 
and the barometrio preesure 20.04 in. 

From Table 41 iis vapor preesure e for 84 deg. ia 1.171 in; of mercury and weight 
of 1 ou. fi. of saturated vapor is 12.37 gr. Henoe the air contains 12.37X0.70-8.60 gr. 
of moisture per cu. ft. and oan absorb 12.37 r-8.60« 3.68 gr. more before condensation 
ensues. If the air is cooled the air will become saturated at the pressure A«« 1.171 X 
0.70-0.82 in. of mercury, which eorresponds to the temperature 78.6 deg. fahr. This 
is the dew point. The weight of the mixture per ou. ft. is obtained from the faetors in 
the last two columns of the table: thus, J>-i(20.04X0.002430) - (0.70X0.00108) - 
0.07226 lb. The volume of 1 lb. is therefore 1/00)7220-13.84 ou. ft. 




THE STEAM ENGINE 



225 



opertiM of Air liiiod with WaUr ¥»por 



Pounds 
per aq. in. 



Weight of water 
▼apor per ou. ft. 



Graina 



Pounda 

ly 



1.326 



X 1000 



0.501^ X 1000 



38 


iiii 


O.0686 
0.0960 
0.1040 
0.1I2S 


2.129 
2.297 
2.4n 
2.669 


0.<X»304 
0.000328 
0.000354 
0.000381 


2.697 
2.686 
2.676 
2.665 


0.184 
0.190 
0.214 
0.231 


40 
42 
44 
46 
40 


0.2A77 
0.2677 
0.2891 
0.3119 
0.3366 


0.1217 
0.1315 
0.142D 
0.1532 
0.1653 


2.872 
3.091 
3.322 
3.570 
3.831 


0.000410 
0.000442 
0.000475 
0.000510 
0.000547 


2.654 
2.644 
2.633 
2.623 
2.612 


0.240 
0.267 
0.287 
0.309 
0.332 


50 
53 
54 
56 
50 


0.3627 
O.390S 
0.4202 
0.4518 
0.4856 


0.1781 
0.1918 
O.2064 
0.2219 
0.2385 


4.110 
4.411 
4.720 
5.054 
5.410 


0,000587 
0.000630 
0.000674 
0.000722 
0.000773 


2.602 
2.592 
2.582 
2.572 
2.562 


0.357 
0.383 
0.410 
0.439 
0.470 


60 
62 
64 
66 
60 


0.5217 

0.5590 

0.6805 

0.644 

0.689 


0.2562 
0.2749 
0.2949 
0.3161 
0.3386 


5.785 
6.043 
6.604 
7.040 
7.52 


0.000827 
0.000883 
0.600943 
0.001007 
0.001074 


2.552 
2.542 
2.532 
2.523 
2.513 


0.503 
0.538 
0.575 
0.614 
0.655 


70 
72 
74 
76 
70 


0.738 
0.789 
0.844 
0.905 
0.964 


0.3625 
0.3879 
0.4140 
0.4433 
0.4735 


0.02 
8.54 
9.10 
9.60 
10.30 


0.001145 
0.001220 
0.001300 
0.001383 
0.001471 


2.504 
2.494 
2.485 
2.476 
2.466 


0.690 
0.744 
0.793 
0.845 
0.099 


80 
82 
04 
06 
88 


1.029 
1.098 
1.171 
1.248 
1.329 


0.5054 

0.539 

0.575 

0.613 

0.653 


10.95 
11.64 
12.37 
13.15 
13.90 


0.001564 
0.001663 
0.001768 
0.001879 
0.001997 


2.457 
2.448 
2.439 
2.430 
2.422 


0.956 
1.016 
1.060 
1.146 
1.216 


90 
92 
94 
96 
90 


1.415 
1.506 
1.602 
1.704 
1.812 


0.695 
0.139 
0.787 
0.837 
0.090 


14.85 
15.77 
16.74 
17.76 
18.79 


0.002121 
0.002253 
0.002391 
0.002537 
0.002690 


2.413 
2.404 
2.395 
2.387 
2.370 


1.290 
1.368 
1.450 
1.537 
1.629 


lOO 
102 
104 
106 
108 


1.925 
2.044 
2.171 
2.303 
2.441 


0.946 
1.004 
1.066 
1.131 
1.199 


19.95 
21.12 
22.35 
23.63 
24.96 


0.002850 
0.00 017 
0.003193 
0.003376 
0.003566 


2.370 
2.361 
2.353 
2.344 
2.336 


1.724 
1.825 
1.931 

2.041 
2.155 


110 
120 


2.580 

3.439 
4.518 
5.874 
7.56 

9.64 
12.19 
15.20 
20.01 
23^.46 

20.75 
29.92 


1.Z71 
K689 
2.219 
2.085 
3.714 

4.737 
5.968 
7.506 
9.335 
11.523 

14.122 
14.697 


26.36 
34.42 
44.45 
56.86 
72.0 . 

90.5 
112.7 
139.4 
171.0 
208.3 

252.1 
261.7 


0.003765 
0.004916.. 
0.00635 .. 
0.00812 .. 
0.01029 .. 

0.01293 .. 
0.01611 .. 
0.01991 .. 
0.02443 .. 
0.02976 .. 

0.03601 .. 
0.03738 .. 


2.328 


2.274 


130 






140 






150 






160 






170 






too 






190 






200 






210 , 















16 



226 



HBAT 





The Bttam KnviiM 
Th« Eanklno Oyeto. 

The ideal Rankine cycle is 
generally employed by en- 
gineers as a standard of 
reference by which the per- 
formance of steam engines 
and steam turbines is mea- 
sured. Fig. 14 shows this 
cyde on the TS and p-V 
planes. AB represents the ^ 

heating of the water in the , ^ t» i • i-i i 

boa«r. BC represents evap- Fio. 14.— Rankme Cycle. 

oration (and superheating if there is any), CD the assumed adiabatic expan- 
sion in the engine cylinder, and DA condensation in the condenser. 

Let «*•• ib, ie, id represent the heat content per lb. of steam in the four 
states A, B, C, and i>, respectively. Then the heat transformed into work, 
represented by the area ABCD, is Qa -i «« — id. 

The heat expended on the fluid is ie — ««; hence the thermodynamic •£&- 
eleney of the cycle is ^i « (i«— td)/(t0~ ia). 

The fteam coxuumption of the ideal Rankine engine in lb. per h.p.-hr. 
is ATr » 2546/Qa  2546/(to — t^. For steam consumptions per kwrhour 
(for use in steam turbine calculations) see p. 355. 

The performance of an engine is frequently stated in terms of the heat used 
per h.p.-hr. For the ideal Rankine engine this is 

Qr - 2646/J&, - 2646 (t\, - t.)/(i« - 1^). 

imelency of the Actual Bngine. Let Q denote the heat transformed 
into work per lb. of steam by the actual engine; then if Qi is the heat furnished 
by the boiler per lb. of steam, the thermodynamic efficiency of the engine 
is E, - Q/Qi. 

The efficiency thus defined is however misleading, as it takes no account of 
the conditions of operation, as regards boiler and condenser pressures, super- 
heat, or quality of steam. It is customary therefore to define the efficiency 
as the ratio Q/Qa, where Qa is the available heat, or the heat that might 
possibly be transformed under ideal conditions. This efficiency for engines 
and turbines ranges from 0.50 to 0.80. The efficiency may also be expressed in 
terms of steam consumed; thus, if Na is the steam consumption of the actual 
engine and Nr is the steam consumption of the ideal Ranikine engine under 
similar conditions, then E ^ Nr/N^ 



Bxample. Suppose the boiler presBure to be 180 lb. per sq. in. absolute, superheat 
IfiO dog., and the oondenaer preBsure 3 in. of xneroury. From the steam tables or dia- 
gram the following values are found: «• i- 1279.0, i^ - 940, t« - 82.9. The 
available heat is (?a •* 1279.9 — 940 - 339.9 B.t.u., and th6 thermodynamio effidenoy 
of the cycle is 839.9/(1279.9 — 82.9) — 0.284. The steam oonsumption per h.p.-hr. is 
2546/339.9 - 7.5 lb., and the heat UMd per h.p.-hr. ia 2546/0.284 « 8960 B.t.u. If 
an actual engine working under the same conditions has a steam consumption of 11.4 
lb. per h.p.-hr., its efficiency is 7.5/11.4 — 0.658, and iU heat consumption per h.p.-hr. 
is 8960/0.658-13.600 B.t.u. 



a I 


\* 




\ 




V 






v^ 


e 


^^ 


3 



FLOW OF COMPRESSIBLE FLUIDS 227 

Calorimetrio Analysis of the Stsam Bnffiiie. The first attempt to 
detennine quantitatively the thermal actions in the steam^ensine ojrlinder is 
doe to Him. By HIm's method, equations are de> 
rived for the heat interchanges between the steam 
and the cylinder walls, and the quantities involved are 
Buch as may be determined from an accurate test. 
In Fig. 15, points 1, 2, 3 and Q represent out-o£E, re- 
lease, compression, and admission, respectively. Let 
Vo, Uu Ut, Ut represent the energy per lb. of fluid at 
ihe corresponding points. ^ Let M denote the weight 
of fluid supplied per stroke, and iif o the weight of Fig. 15. 

fluid caught in the clearance space. Let Q«, Qh, Q«, 

Qd denote respectively the quantities of heat absorbed by the cylinder walls 
from the fluid during the processes represented by o, b, c, and d on the diagram ; 
and let Wa, Wb* TTe, andWd denote the external work performed during the cor- 
responding parts of the cycle. Let Q denote the heat brought into the cylinder 
per stroke by the working fluid; thus, Q « Aft, where t is the heat content of 
the entering steam. Finally, let i' denote the heat content of the liquid at the 
pressure of the exhaust steam, O the weight of condensing water used per 
SUt>ke, and f, t" the initial and final temperatures of the cooling water. 
Then the heat interchanges are expressed by the following equations: 

QwQ +Uq-Ui - AWa. Qft ^Vi-Ut" AWh. 

Oe - 17, - r^s - Mi ^0(t" - O + AWc* Qd '-Vt''Uo + AWd. 

In getting the expressions for Uo, Ui, etc., there are five unknown quantities, 
namely Mo, and the four qualities 20, xi, xs, Xf. Between these there are four 
relations. Let Vq denote the volume of the clearance space, and Vi, Vs, Ft 
the spaces swept through by the piston up to the points 1, 2, 3. Also let s a 
f" — t^, the difference between the voltime of vapor and liquid. Then 

Vo - if o(«o»o +0. To + Fi - (Af + MoHxiai + «0. 

^0 + F, « (If + Afo)(xt«, + vO. T^o + Va - Afo(xa«s + t^. 

If one quality be known or assumed, these four equations give JIf and the 
remaining qualities. It is usually assumed that the steam in the cylinder is 
oearly or quite dry at the beginning of compression, hence xs »■ 1. 

For an ezhauative treatment of the calorimetrio analysis of steam engines, see Pea- 
body's "Thermodynamics," 5th ed., chap. xi. 

BETBiaBBATION 

Air Befiigeratioii. When air is used as a medium for refrigeration the 
re^'ersed Joule cycle is employed (see p. 206). The refrigerating machine has 
four essential organs: 1. A compressor in which the air is compressed. 2. 
A cooling coil surrounded by water. 3. An expansion cylinder. 4. A brine 
coil. Fig. 16 represents ideal p-V and TS diagrams. Point A represents the 
state of the au* entering the compressor from the brine coil or cold room, AB 
represents the compression, BC the cooling of the air at constant pressure, 
CD the expansion of air in the expansion cylinder, and DA the absorption of 
heat by the air during the passage through the brine coils. In the p-V dia- 
Sram ABEF represents the indicator diagram of the compressor, ECDF that 
of the ex]>ansion cylinder. The difference, area ABCD, represents the work 
that must be furnished from external sources. In the TS diagram area 
BiBCCi represents the heat absorbed from the air by the cooling water, area 
CxDABu the heat absorbed by the air from the brine, and area ABCD the heat 



228 



HEAT 



equivalent of the work required to drive the machine. The temperature at 
point A must be somewhat lower than the brine temperature, the tempera- 
ture at C somewhat above the temperature of the cooling water. With the 
open-cycle machine the lower pressure pi is atmospheric pressure; with a 
closed-^ycle machine, as the Allen dense-air machine, p\ may be 40 to 60 ib. 
per sq. in. and pi as high as 200 lb. per sq. in. 

Let Q « heat in B.t.u. absorbed from brine (or cold room) per min. 
M -■ weight of air circulated per min., lb. 
Cp  0.24, specific heat of air at constant pressure 
W ■» work required per min., ft.-lb. 

Fe » displacement volume of compressor cylinder, cu. ft. 
F« xB displacement volume of expansion cylinder, cu. ft. 
n * number of working strokes per min. 

' With assumed adiabatic compression and expansion the following relations 
hold: 

n/Ta « TJTi - (p,/pi)(* - 1)/* M = Q/Cp( T. - Td). 

w « 778Q(n - r.)/r«. hjp, « TF/33.000. 

Fc - AfBra/144pin. F, - MBTd/l^Vxn. 




eooLiNQ nmw 



Ci Bt 

Fio. 16. — Air Refrigeration Cycle. 




FiQ. 17. — Vapor Compression 
Hefrigevation Cycle. 



Vapor Compression Machines. The essential organs of a vapor com- 
pression system are the same as in the system using air, except that the expan- 
sion cyclinder is replaced by an expansion valve through which the liquefied 
medium flows from the high-pressure condensing coils to the low-pressure 
brine coils. The cycle of operation is best shown on the TS plane (Fig. 17) . 
The point B represents the state of the refrigerating medium leaving the brine 
coils and entering the compressor. Usually in this state the fluid is nearly- 
dry saturated vapor, that is, point B is near the saturation curve 5". EC 
represents the adiabatic compression, during which the fluid is Usually super^ 
heated. In the state C the superheated vapor passes into the cooling coila 
and \B cooled at constant pressure, as indicated by CD, and then condensed 
at temperature Tt as shown by DE, The liquid uqf flows through the expan^ 



f 



RBFRIGB RA TION 229 



lion valve into the brine coils. This is a throttling process and the final-state 
point A Is located on the Ti-line in such a i>o8ition as to make the heal content 
for state A {^ area OHOAA\) equal to the initial heat content at E ( » area 
OHEBx). The mixture of liquid and vapor now absorbs heat from the brine 
ind vaporises, as indicated by AB, 
The heat ftbiorbed from the brine; represented by area AiABCu is 

Ql « t6 - t, « t6 - U 

The heat rejected to the cooling water, represented by area CiCDEEi, is 

Qi -= ic - u * cpiTc - Td) + n 

vhere n denotes the latent heat at the upper temperature Tt, and e^ the spe- 

eilic heat of the superheated vapor. The work that must be supplied per 

pound of fluid circulated is F » J(Qt - Qi) « J(ic - h). 

The ratio JQi/W « (4 — if)(ie ~ k) is sometimes called the coefficient of 

jperf or mance . 

r If Q denotes the heat that is required to be absorbed from the brine per 

kr., then the weight of fluid circulated per hour is Af » Q/(k — i«) ; or, if 

^ is taken on the saturation cxirve, M =Q/{%'\ — I't). 

The work per hr. is l»^ - JM(ic - i"i) ^JQiic - t"i)/(t"i - »'«) ft.-lb., 
%nd the h.p. required is H -> Q(t'« - t"i) /2546(t"i - t's). 
r If v"i is the volume of the saturated vapor at the temperature Ti in the brine 
polls, and n the number of working strokes per min., the displacement vol- 
ume of the compressor cylinder is V » Mv*'i/60n, 

The values of i"i. it in the preceding formulas are found in the tables of satu- 
rated vapors. The heat content t« of the superheated vapor may be deter- 
Ained in the ease of ammonia from Table 36 for superheated ammonia. 

▼apon Used in Refrigeration. The three vapors that are principally 
used for refrigeration are ammonia (NHs), carbon dioxide (COs) and 
lulphur dioxide (80s). The temperatures of the working fluid in the con- 
densing and brine coils are fixed by the temperature of cooling water and the 
temperature at which the brine b to be kept, respectively. Since for a vapor 
Lhe pressure depends on the temperature only, the discharge and suction 
preesuree that must be used are dependent on the properties of the fluid 
mployed. Another consideration in the choice of a fluid is the volume of 
luid required for a given amount of refrigeration. In general, the fluid for 
vhicb the ratio (latent heat : specific volume) is greatest requires the smallest 
cylinder displacement per unit of refrigeration. 

Taking 70 deg. fahr. as the temperature of the fluid in the condensing coils 
ind 15 deg. as that in the cooling coils, the following are the conditions for 
he available vapors: 

treasures, lb. per sq.in.: NHi COs SOs Ethyl Methyl Nitrous Pictet's 

chloride chloride oxide fluid 

uction 42.7 391 15.2 6.0 25.0 431 20.3 

Nuehante 129.2 847 49.6 20.0 73.3 832 51.6 

telative volume per 
unit weight of refrig- 
eration 4.4 1 12.0 .... .... .... .... 

^ith SOt the pressures are low but the volume of medium is comparatively 
irge, wiiile with COs small volume is accompanied by extremely high pressures. 

Mmtrigtmktion Produced by Ammonia and Carbon IHoadde. Tables 
'2 and 43 give the refrigeration produced in B.t.u. per h.p.-hr. under dif^ 
tront conditions. It is assumed that there are no losses in the cycle, except 



230 



HSAT 



that inherent in the lue of the expansion valve. The temperature at ike 
top of the column ia that of the vapor in the brine ooil» while at the side is 
given the temperature of the condensed fluid as it enters the expansion valve. 
For example, under a pressure p of 150 lb. with a temperature (q of 20 deg. 
fahr. in the brine coils and a temperature of 70 deg. fahr. at the expansion 
valve, the refrigeration produced in an ammonia machine without losses is 
17,800 B.t.u. per h.p.-hr.; this is 90 per cent of the refrigeration that would 
be produced if the liquid temperature were reduced to 20 deg., the tempera- 
ture in the brine coils. 



Table 41. Befrifferatioii Produced by Ammonia in B.t.u. per H.p.- 

Hour 



Temp, at expansion cock, 
degrees fahr. 


Vspor temperature fo in deg. fahr. 


30 


20 


10 


-10 


-20 




Condenser pressure p -> 100 lb. per sq. in. 


fa 
50 


45.400 
43.600 


30.900 
29.300 


23350 
21.950 


21.000 
19.100 


17.150 
15.500 


1Z90Q 
11350 




p - 150 lb. 


50 
70 


25.000 
24.100 
23.300 


19.900 
18.700 
17.800 


15.900 
14.900 
14.250 


14.400 
13.050 
IZ450 


12.400 
11.000 
10.650 


10.101 
8.851 
8301 




p - 200 lb. 


50 
70 
90 


18.300 
17.800 
17.000 
16.100 


15.200 
14.400 
13.800 
13.000 


13.050 
12.200 
11.600 
11.150 


11.700 

10.650 

10.100 

9.650 


10.350 8.600 
9.150 7350 
8.750 1 7.250 
8.250 6.850 




p - 250 lb. 


U 
50 
70 
90 


15.100 
14.600 
14.000 
13.300 


12.900 
12.100 
11.500 
11.000 


11.400 

10.600 

10.050 

9.650 


10,250 
9.300 
8.800 
8.450 


9.150 
8.050 
7700 
7.350 


7.800 
6.900 
6.500 
6.200 




p «* 300 lb. 


50 
70 
90 


13.400 
13.000 
12.500 
11.900 


11.200 
10.950 
10,400 
10.000 


10.200 
9.450 
8.995 
8.650 


9.250 
8.450 
8.050 
7.650 


8300 
7.400 
7.100 
6J50 


7.150 
6.300 
6.000 
5.700 



REFRIOBRATION 



231 



'able 4S. Bofrif aration Produced by Carbon Dioxide in B. t. u. per 

H.p.-Hoar 



^ttperature »t ezpanaton 
cock, dtff, f ahr. 



50 
60 



to 
SO 
60 
70 



f« 
SO 
60 
70 
80 
90 



U 
SO 
60 
70 
80 
90 



U 
SO 
60 
70 
80 
90 



Vapor temperature 1% in deg. fahr. 



30 



20 



10 



-10 



-20 



32.600 
29.650 
27.600 



22.600 
20.800 
I9J50 
17.800 



16.600 
IS.350 
14.450 
13.600 
12.650 
11.450 



14.250 
13J00 
12.400 
11.750 
10.900 
10.000 



Condeneer preeeure p  800 lb. per eq. in. 



26J0O 


21.750 


18.650 


15.600 


23.650 


19.000 


16.150 


13.450 


21.600 


17.150 


14.350 


M.6S0 



10001b. 



18.800 


16.050 


13.750 


12J00 


17300 


14.250 


12.000 


lOJSO 


15.850 


12.900 


10.750 


9.150 


14.750 


12.050 


10.050 


8.400 



12001b. 



14.700 


13.050 


11.550 


10.350 


13.550 


11300 


9.950 


8750 


12300 


10.600 


9.050 


7.850 


11.700 


9.850 


8.550 


7.250 


10.800 


9.150 


8.000 


6.750 


9.750 


8.300 


7.100 


6.050 



14001b 



12700 


11.400 


10350 


9.250 


11.650 


10.200 


8.950 


7.900 


10.900 


9.350 


8.100 


7.050 


10.150 


8.750 


7.600 


6.600 


9.600 


8.200 


7700 


6.200 


8.750 


7.550 


6.600 


5.650 



16001b. 



13.150 
I2.20O 
11.450 
10700 
9J00 
9.150 



11.600 


10.250 


9.950 


8.500 


10.600 


9300 


8.300 


7.400 


10.000 


8.600 


7.500 


6.600 


9750 


8.150 


7.000 


6.250 


8.750 


7.650 


6700 


5.850 


8.200 


7.150 


6.250 


5.850 



13.300 

11.050 

9350 



10700 
8.650 
7.500 
6.950 



9.250 
7.500 
6.500 
6.150 
5.600 
5.150 



8750 
6.850 
6.150 
5.650 
5.400 
5.000 



7350 
6.500 
5.850 
5.500 
5700 
•4i950 



rxow or comprbssibls fluids 



Important e^amplee of the flow of compressible fluids are the following: 
I. The flow of air and steam through orifices and short tubes or nozzles, as 
n the steam turbine. 2. The flow of oompressed air. steam, and illuminating 
sas in long mains. 3. The flow ot low-pressure gases, as furnace gases in 
luctB and chimneys or air in ventilating duots. 4. The flow of gases in 
noTisg channels, as in the centrifugal fan. 




232 HBAT 

Notation. 

Let M a weight In lb. of fluid flowing past a given section per aeo. 

F "■ area of aection, sq. ft. 

IT « mean velocity in ft. per sec. at the given aeotion. 

h ^ height of cross-section above an assumed datum. 

V  volume per unit weight (cu. ft. per lb.). 

p ■* pressure of fluid at given section, lb. per sq. ft. 

u "■ internal energy of fluid, B.t.u. per lb. 

i n heat content, B.t.u. per lb. 
Qu "- heat entering the flowing fluid between sections P\ and /«. 
R^ « energy expended in overcoming internal and external 
friction between sections F\ and Ft. 

The eroBS-Beotionfl of the tube or channel are do- 
noted byFipFt, etc., Fig* 18, and the various mag- 
nitudes pertaining to these sections are denoted by 
corresponding subscripts. Thus, at section Fu the 
velocity, volume, pressure, energy, are respectively "Fiq, 18. 

«n» vii Pit ui; at section F% they are tos, oi, ps, ui. { 

Fundamental Iqufttions. The condition of continuity isexpressd 

by the equation 

M - Fiwi/vx « Fiw»/vt, or dv/v - {dP/F) + (dto/w). 

The principle of conservation of energy leads to the equation 

!(«»»« — wii)/2(f] + Jim — ui) + pnDt — pioi + ht — hi — JQu; 

or, introducing the expression for heat content <  u + Apo, 

l(wt* - wi*)/2o] '+ J(it - ii) + Ai - At - JQit. 

If the sections are taken an infinitesimal distance apart, this energy equa- 
. tion takes the form 

(wdw/g) + Jdi + dA « JdQ, 

A second fundamental equation is obtained by the further applicatioa 
of the energy equation, taking the friction work R into account. It is 

dQ + AdR » du + Apdv » (tt - Avdp. 

Combining these last equationB* 

(wdw/g) +vdp+dR+dh^(k 

Usually hi -^ k% and Qn are so small aa to be negligible. In this case H&e 
two fundamental equations become 

(toi« — wi*)/2o =» J(tt — t»)a (wi« — wi*)/2o - — Jl*^P — -Bit 

For gases, ii — it - Cp (^» ■* ^^i) « Ak(pivi - pfot)f{h^ 1); hence 
I(fwt - wii)/2^1 « Jcp{Ti - TV) - k{pivi - piot)/{k — 1). 
For a mixture of vapor and liquid, % ■■n*' + xr\ therefore 
[{w%t - «i«)/a^] - ^»'i + avt - (»'t + »ir*)l. 



now Through Orifleei 



A ease of 8i>ecial importance is the flow of a gas or vapor k-^lh 
from a reservoir into a region of lower pressure through p, i \ ^t 
nn orifice or ghort tube. In Fig. 19 the section Fi is 
taken within the reservoir where the pressure is pi, and the 
section Ft is taken at the plane of the orifice. The pressure ^^- ^^- 






FLOW THROUGH NOZZLES 233 

At this aection is taken as jh, and the pressure in the region into which the 
Jet is flowing is taken as po- The initial velocity 101 is so small that vn* may 
be ne^tooted in com|>arison with toi*. Hence _.^ 

wi«/2y - J(tt - ii). and tin - 223.7\/*i - «• 

The character of the flow depends on the ratio pt/pt, and two distinct eases 
may be noted. Let the law of frictionless adiabatic expansion of the fluid 
ki question be pivi* « po^ a const. For gases, n ^ k^ for steam n has the 
Taloe given in Table 40, p. 223, and for superheated steam or ammonia n 

may be taken 'as 1.3, Take p» - pi[2/(n + l)f»/^» - *>; then pm is the 
srltioal preuure. For gases pm/vi ^ 0.53, approz.; for saturated steam 
the ratio is about 0.575; and for moderately superheated steam, about 0.55. 

Case 1. po>Pm* Then pi •■ pot and the discharge M is given by the 
equation 



"-'^V^-.-^J-d:)^! 



Thus the weight flowing per second dQ;>ends upon the two pressures pi 
and po> _ 

Casb 2. pQ ^ pm. Then pa  p«, that is, pi remains constant whatever 
lowor value the pressure po may take. In this case the discharge is 



\» 4- 1/ \ n + 1 t>i 



Hence the discharge depends upon pi only and is not influenced by the pres- 
sors Po. 

7ormul» for Discharge of Air. When the back pressure po exceeds 
the oritioal pressure pm — 0.53 pi, 

ki which p and T refer to the air in the reservoir. Values (p/po)^*"* are given 
on p. 203. [(»— l)/n «» 0.286 when n » 1.4] 

When pt is equal to or less than PmtM'' 0.63 Fp/y/T. 

For a small difference of pressure, M — l.lF\/(p/T)(p — po) 
In these three formulsD F is to be taken in sq. in. when p is taJcen in lb. per 
•q. in. The discharge as calculated by the formula should be multiplied by a 
eoeflksient of discharge to take account of friction, contraction, etc. 
Trom the experiments of Zeuner and others, the following mean- values of 
this coefficient are obtained: 

Orifices in a thin plate 0.64 

Short oyifndrical pipe, inner comers not rounded . 76 to . 84 

Well-rounded mouthpiece . OS 

FormuUs for Ilischarg • of Saturated Steam. When the back 
pressure po is less than the critical pressure pm, the discharge depends upon 
the area of orifice F and reservoir pressure p. There are three formula 
indely used to express the discharge O in terms of P and p, as follows: 

L Napier's equation^ itf ^ Fp/70. 

2. Grashofs formula, AT » 0.0165F p^'^. 

3^ Bateau's formula, M - Fp(16.367 - 0.06 log p)/1000. 

In these formulo F is to be taken in square inches, p in lb. per sq. in. 
Napier's formula if merely convenient as a rough check. The coefficient 



234 



HEAT 



oi diacharge may be taken as 1; that is^ no correction is required. 



Table 44. Values of p***' for tTse in Oraghof '■ TormuU 



p 


jfi.ti 


P 


pt.91 


P 


jfi.97 


P 


^■"' 


15 


13.0 


50 


44.5 


110 


95.5 


225 


191.2 


28 


18.3 


55 


46.8 


120 


104.0 


250 


212.0 


25 


22.7 


60 


53.1 


130 


112.4 


275 


232.0 


30 


27.1 


70 


61.6 


140 


120.7 


300 


253.ff 


35 


31.5 


80 


70.1 


150 


129.1 






40 


35.8 


90 


78.6 


175 


150.0 






45 


40.1 


100 


87.1 


200 


170.6 








FiQ. 20. 



When the back pressure p9 is greater than the critical pressure Pm tlis 
velocity and discharge are found most conveniently from the general f ormulfB 
of flow. From the steam tables (p. 209) or from I 

the Mollier chart (p. 214) find the initial heat 
contentii and the final heat content t'o after adia- 
batic expansion; also the specifio volume «oin the 
final state. See Fig. 20. Then 

w « 223.7Vti~-7o and M « Pw/vo. 

The same method is used in the case of steam 
initially superheated. 

Kxample. Required the discharge through an orifioe 
>1 in. in diameter of steam at 140 lb. per iq. in. super* 
heated 110 deg.; back preasure, 90 lb. per aq. in. 

From the Mollier chart. »'i m 1253, and it » 1213. 
Also u - 6.26 cu. ft. 

10 - 223.7 Vl263 - 1213 « 1413 ft. per sec 
P -:O.1964 0q.in. • (0.1964/1^ sq.ft., 
M « Pip/vo - (0.1964/144) X (1413/5.26) * O.S06 lb. per seo. 

Flow Through Diverging Nossles. At the throat, or smalleet erase* 
section of the noszle (Fig.. 21) the pressure takes the value pm " 0.57 p^^ 
The weight discharged is fixed by the area Pm of the throat and the reservoir 
pressure pi, and may be found from Grashofs or Rateau's formula. Tlie 
diverging part of the nozzle permits further expansion to the back pressure 
p«, the velocity of the jet meanwhile increasing from Vm, the critical velocity 

at the throat, to tro givei;! by the fundamental equation io« * 223.7vu — <•. 

The frictional resistances in the noszle have 
the effect of decreasing the jet energy w^/2if and 
correspondingly increasing the energy and heat 
content of the flowing fluid. Thus, if t« is the ^ 
heat content in the final state with frictionless 
expansion, t'o(>to) is the heat content when fric- 
tion ia taken into account; hence w't^/Zg a 
/ (ti — i'o) is less than W9*/2g = J(%i — u). The 
loss of kinetic energy in B.t.u. is t% — io, and the 
ratio of this loss to the available kinetic energy, that is (i't — to)/(«i — ' t*)» £ 
denoted by y. For values of y, see p. 235. 

The design of a noisle for a given dieoharge M with pressure pi aetdi 
pa is most conveniently effected with the aid of the Mollier chart. Determinei 
Pmt the critical pressure, and t'l, t», ft, assuming frictionless flow. Then 

vom - 223.7Vu - i», and v>\ m 223.7V(1 - V) (* - <•). 




Fig. 21. 



STEAM FLOW I.V PIPES 



235 




i\ . 1251 



ft«.119S 



Fia. 22. 



)7est find vm anci «V Then, from the equation of continuity, 

Fm -»(?»«/»», andF't -G^'o/w'*- 
The foUowing example fllustrates the method. 

Wiample. Requind the throat and end Motions of a nonle to deliver 0.7 lb. of 
Heam per aeo. The initial preaeure ia 160 lb., the back preeaure 15 lb., and the steam ia 
iaitlally niperbeatad 100 deg.; y ^ 0.15. 

The critical pieeaaie ie 160 X 0.55 - 88 lb. 
On the MoUier chart (Fig. 22) the point A repre* 
anting the initial state is located, and line of coih 
itant entropy (a f rictionlese adiabatio) is drawn 
from A, Tlds cuts the curves p -■ 88 and p » 15 
li the points B and C, respeotirdy. The three 
ffthiet of % are found to be n - 1251, »» - 1198, 
Ik « 1065. Of the available drop in heat con- 
tesl, ti ~ to -i 186 B.t.u., 15 per cent, or 27.0 
B.tu. is lost through friction. Hence, CD > 
S7.0 is laid off and D is projected horizontally 
to point C on the curve p * 15. Then C repre- 

IBBts the final state of the steam, and the qufJity ia found to be s » 0.04. The speolfio 
tolame in the state C is 26.27 X 0.04 » 24.7 cu. ft. Likewise the specific volume for 
Ibe stote B is found to be 5.2 ou. ft. 

For the vciocities at throat and end sections, 

w» - 223.7\ /x251 - 1198 » 1629 ft. per sec. 

wt - 223.7V186 - 27.9 - 2813 ft. per sec. 
Fm « (0.7 X 5.2)/1629 -^ 0.00223 sq. ft. - 0.322 sq. in. 
F% - (0.7 X 24.7) /2813 t^ 0.0061 sq. ft. - 0.88 sq. in. 
The dxametera are d»— 0.64 in. and d« — 1.06 in. 

Velocltj CoefBclentt. Lots of Energy y. On account of friction losses 
flie actual velocity w attained by the jet is leas than the velocity w* cal- 
culated under ideal conditions. That ia, w *■ xw%^ where a; (< 1) ia a velocity 
SDefficient. Evidently the coefficient x is connected with the coefficient y 
(^ p. 284), giiving the loss of energy by the relation y » 1 — 2*. 
^ For oriflees in thin plates, the experiments of Zeuner on air and of 
^utennuth and Bendemann on saturated and superheated steam indicate 
that X has the value of 0.97 to 0.975. 

For How through noBBlos, Stodola states that the energy loss varies from 
f * 0.05 for shor^ tubes to y "■ 0.15 for long tubes. The most comprehen- 
ire experiments in this field are those of Briling {MiUeil, itber Forsch.-arh., 
16) and of Josae and Christlein {ZeiL Ver, Deuisch. Ing,, 1911, p. 2081). Briling 
wad dightly superheated steam and two nosiles, one cylindrical with a 
diam. of 0.254 in. and length of 1.18 in., the other a slightly converging nos- 
de with 8 minimum diam. of 0.84 in. For the cylindrical tube he found 
a • 0.95; for the convergent tube x increased from 0.92 to 0.905 as the 
Telocity increased. These results indicate an energy loss of 10 per cent in 
the cylindrical tube and of 7 to 16 per cent in the convergent tube. The 
azperiments of Josse and Christlein were made on 6 De Laval noaales having 
fBtios of maximum to minimum sectional areas ranging from 1.185 to 12.94. 
Under the most favorable conditions, with a tube properly proportioned for 
I the pressure drop, the experiments showed a value of s "^ 0.94 for a velocity 
of 2000 ft. per aeo. and a value around 0.95 for velocities of 2500 to 3500 ft. 
per see* Taking x  0.945 as a mean value, the energy loas ia, 

y-l-««-l- 0.945* « 0.107. or 10.7 per cent. 

Joase and Christlein alao made experimenta on the friction loaa in a aet of 
three guldo Tsnos, which take the place of noulea in turbinea of the Rateau 



236 



HEAT 



type. Under f avoraUe oonditions with alightly superheated steam the meat 
value X •■ 0.923 was found. The corresponding loss of energy is if ^ 0.141 
or 14.8 per cent. With high superheat and a velocity of 2200 ft. per sec., tfas 
value X ■> 0.05 was obtained, but at about 800 ft. per sec. x dropped to aboiA 
0.85. Rosenhain's experiments give values of x for sevend tsrpes 4f 
nozsles. Table 45 gives data and results (see Peabody's " Thermodynamics," 
p. 442). 

Table 46. Values of the Velocity Coefficient x for Various Types of 

Noaales 

(Rosenham. Proe. Inat. C. E., vol. 140. p. 199) 



Ratio of greatest to 


Taper 


InitUI 


Velocity 


' Lou of 


least diameter 


pressure 


coefficient, x 


energy, y 


1.56 


1:20 


ISO.O 


0.946 


0.105 


1.96 




:12 


275.0 


• « • • • 


• • • • • 


1.36 




:I2 


97.5 


0.972 


0.045 


1.28 




:I2 


80.0 


0.903 


0.185 


1.39 




:30 


105.0 


0.913 


0.166 


1.32 




:30 


90.0 


929 


0.137 


1.26 




:30 


77.5 


0.901 


0.188 


1.19 




:30 


62.5 


0.914 


0.165 


1.12 




:30 


50.0 


0.914 


0.165 



Lewioki's experiments on small divergent noules showed values of a 
lying around 0.955 to 0.96. The loss of energy was therefore 8 to 9 per cent 

Flow of Steam in Pipes. Since for the relatively short pipes ordinarilf 
used to convey steam the drop in pressure is small, the approximate formuU 
p' » cMjjvd is applicable. In the case of saturated steam the product pti* 
(y* •" specific volume) remains nearly constant for a considerable range d 
pressure. Taking a mean value for thi s product, the equation of flow takes 

the forms p' ^ KcWL/pd^^ M =^y/Tp^pcfi/KcL, Evidence regarding the 
value of the coefficient e is conflicting. The experiments of Eberle indicate 
that c is practically constant for aU conditions. On the other hand, expeii- 
mente conducted for the Bavarian Revisiozi-Verein seem to show that the 
empirical formulas given by Fritzsche for air apply also to saturated and 
superheated steant. In the formulse given by Martin, Hawksley, and Hurst, 
c is taken as constant; the formulcs of Babcook and Unwin make c vary wi^ 
the diam. of pipe according to the law c « K[l + (3.6/<2)]i with d in inches. 
A comparison of different formulas is made by Professor Qebhardt in Power^ 
June, 1907. See also Lucke's "Engineering Thermodynamics," p. 1117.'^ 

Eberle's value of the coefficient c is 2.225 X 10~< with d in ft. and 2.667 X 
10~' with din in. The formula used by Martin and others iap' =* KM^L/Dd*, 
and with M in lb. per min. and d in in., k has the following values: Martiup 
0.0003133; Hawksley, 0.0003370; Hurst, 0.0003126. 

Baboock'8 formula is p' - A; [1 + (3.6/d)](Jlf <L/I>d*), with k « 0.0001321 
(M in lb. per min. and d in in.). 

As an sxample, take saturatsd steam at a prssture of 80 lb. per sq. in. flowing in • 
main 500 ft. long and 6 in. in diam. Under theae conditions T/pw » 0.129, and from 
the table of coefficients e « 1.69 X 10~*. The specific volume is 6.47 cu. ft. per lb. 
and D - 0.1829 lb. per ou. ft. M « 2.7 lb. per sec. « 162 lb. per min. 

By Babcock'a formula, p' « 1.96 lb.; by Kberle's p' - 2.28 lb., and by Martin's 
formula, p' - 2.89 lb. 



THROTTLIXQ 237 



ThrottUBff 

Throttling or Wiro-drawing. When a fluid flows from a region of higher 
presure into a region of lower preasure through a valve or conetrioted paasagt* 
it ii said to be throttled or wire-drawn. Examples are seen in the passage 
of steam through preasure-reduoing valves, in the flow through ports and pas- 
aagee in the steam encrine, and in the expansion valve of the refrigerating 
machine. 

The genoral equation applicable to throttling prooeggei is derived 
from the general equation for the flow of fluids, namely, 

(tDi« - wi^f2a - (ti - it) J. 

The velodtiee w% and toi are practically equal, and it follows that ii  it; 
that is, in a throttling process the initial and final values of the heat content 
sreeqnaL 

For a miztoje of liquid and vapor, t a {' 4. xr, henoe the equation of 
throttling is t'l + xin * »'a+ xtfk In the case of a perfect gas,< «■ CpT* + Ut 
hence the equation of throttling is CpTi + t* "■ CpT% + io, or Ti -^ T%^ 

Joule-Thomion Xfleot. The investigations of Joule and Lord Kelvin 
•bowed that an actual gas experiences a drop in temperature when throttled. 
The ratio of the observed drop in temperature to the drop in pressure, that is, 
ir/dp, is the Jonle-Thomion coefficient. According to these investiga- 
ton, this coefficient varies inversely as the square of the absolute tempera- 
ture, but is independent of the pressure. More recent experiments indicate, 
however, that the coefficient also varies with the pressure. 

The cooling ellect produced by throttling has beoi applied by Linde 
to the liquefaction of gases. 

Loes Due to Throttling. A throttling process in a cycle of operations 
alwasrs introduces a loss of efficiency. If To is the temperature corresponding 
to the back pressure, the loss of available energy is the product of 7*o and the 
ioerease of entropy during the throttling process. The following example 
iUustrates the calculation in the case of ammonia passing through the expan* 
aon valve of a refrigerating machine. 

Iiample. The liquid ammonia at a temperature of 70 deg. fahr. passes through the 
vaivs into the brine eoil in whioh the temperature is 20 deg. and the pressure is 47.75 lb. 
pwiq. in. The initial heat content of the liquid ammonia is t'l «• 42.1, and thereforf> 
the final heat content is i*% + x^t — — 12.6 + 556.3x* « 42.1, whence n « (42.1 + 
12.6)/556.3 - 0.0985. The initial entropy is s'l « 0.0813. The final entropy is 
,', + {xtrt/Tt) - — 0.0262 + 0.0985 X 1.1699 - 0.0880. r» - 20 + 460 - 480; 
hoMe the loss of refrigeratinc effect is 480 X (0.0880 - 0.0813) >- 3.2 B.t.u. 



SECTION 3 
FUELS AND COMBUSTION 



FUEL OIL BURNING 



BY 



JOHN 8HOBIB BUBBOWS, Consulting Engineer for CaBtner, Curran A 
Bullitt; Mem. U. S. Fuel Administration, U. 8. Geological Survey, 
U. 8. Government Coal Testing Plant; Mem., A.S.T.M., Inter. 
Hy. Fuel Assn. 

FBAMK WABD 8TBBLINQ, Lieutenant Commander, XT. 8. Navy, Design 
Divisipn, Bureau of Steam Engineering, Navy Department; Sec'y 
Treas. A.S.N. E.; Mem. Soc. Nav. Arch. A Mar. Eng. 

ALBERT M. PENN, Lieutenant Commander U. S. Navy. In Charge of 
Navy Fuel OU Testing Plant; Mem. A.S.N.E. 



CONTENTS 



COAX. 

Bt J. a BURROWS 



Paob 



Composition 241 

Aaaljrsis 241-243 

Cbusification 243 

Marine Coals 243 

Selection and Inspection of Coal for 

^f arine Use 245 

Spontaneous Combustion and Stor- 
age 245 

U.S. Navy Coal 246 

Standard Steaming 247 

fismpling 247 

OIL WVEL 

By F. W. STERI.ING 

Petroleum and Fuel Oil 250 

Pioperties of Petroleum 251 

CoetB, Coal and Oil Fuel 252 

Oil Fueling SUtions 253 

Advantages, Coal and Oil Fuel 254 

Physical Properties 256 

Heating Value 256 

Viacosity 256 

Vlacosity Conversion Curves 260 

Bpecific Gravity 262 

Bzpanrion 262 

Sipecific Heat 267 

Flash Point 268 

PIre Point 269 

Centrifuge 271 

Conservation 273 



Safety Precautions: 

Burning 

Carrying 

Loading 



Page 

274 
275 
276 



commiecxal qasolxni 

Bt f. w. sterling 

Properties 

Specifications 

Tests 

C0BCBU8TI01I 

Bt F. W. sterling 

Air Required for 

Excess Air 

Volume Contraction 

Combustion Products 



277 
277 
278 



279 
280 
280 
280 



on. FUXL Bu&imia 

Bt albert M. PENN 

Atomisation and Atomisers 

Air for Combustion 

Air Registers 

Boiler Furnace Design 

Furnace Insulation 

Relations Between Rate of Com- 
bustion, Heating Surface, Furnace 
Volume and Air Pressure 

Fuel Oil Equipment 

Boiler Room Instruments 

Operation 

Precautions 



281 
287 
292 
297 
297 



299 
301 
315 
322 
326 



239 



f 



COAL 

BY 

J. S. BURROWS 

BznaiDrces: Publications of the U. S. Bureau of Minee on analyses of coiU. combus- 
tion tests and firing methods. U. 8. Geological Survey for descriptions and maps 
of V. S. eoal fieids. BuUelina of the UHnois Engineering Experiment Station on ooal 
fuid combustion. Lewes, ''Carbonisation of CoaL" Dyson, "Praotical Marine 
Kngineoring,** Aldrich Publishing Co. The Coal Catalogue, Keystone Consolidated 
Pnblishing Co. for lists of producers. Welch Coal Annual, Cardiff, Wales, for foreign 
.coals. Coal Age. "Black Diamond*' and Coal Trade Journal for market reports. 

Dellnitioh. Coal is an agglomerate of the solid degradation products 
of decayed vegetation which consisted of sedges, reeds, tree ferns, club 
mosses and trees akin to the pine, together with such of the original bodies 
as have resisted to a greater extent the actions of time, temperature and 
pressure to which the material was subjected in the transformation to coal. 

Composition. The elementary chomiGal oongtituonts of coal are 
carbon, hydrogen, oxygen, nitrogen and various mineral constituents which 
make up the ash. These elements are combined in coal in some of the most 
eomplex substances known to organic chemistry. The determination of the 
l^reentages of carbon, hydrogen, oxygen and nitrogen is known as an "Ulti- 
Siftte AmUsriiS." This form of analysis is seldom necessary in practical 
rork and is mainly used in chemical investigations of the organic substance 
of ooal. 

For fuel and other practical purposes, coal is considered as being composed 
of moifltoie, volatile matter, fixed carbon, ash and sulphur, a statement of the 
percentage of each of theee items being known as a "Prozizaate Analygis." 

Moisture consists of the natural water combined in or held mechanically 
in the coal particles before mining, plus such atmospheric moisture and rain as 
may have been added while in transit or in storage. The amount of moisture 
ill a given coal varies greatly after it is mined, increasing or decreasing in a 
short period of time according to atmospheric conditions. 

Volatile Matter consists of many complex combinations of mainly 
earbon, hydrogen and oxygen, which form during the early stages of the 
combustion process and which are manifest in the gases and tarry or smeky 
vapors issuing from the surface of a fuel bed. Under suitable conditions 
volatile matter can be burned to prevent smoke, but not all of the volatile 
matter is combustible. 

Fixed Carbon is virtually coke, or that portion of the coal (minus the ash) 
which remains after distillation of volatile matter. In laboratory work, 100 
ninus the sum of the amounts of moisture, volatile matter and ash is arbitrarily 
termed the amount of fixed carbon. Thus all possible errors are thrown into 
this item, which, however, is of the least importance in fuel oalculatiors or 
comparisons. 

16 241 



242 COAL 

Ash oonaiflts of the nonoombustible residue remaining after combustion 9 
complete. Its composition and amount vary greatly, according to the origiD 
and nature of the coal from which it is derived. There are two sources of 
ash: from the coal substance itself, which is known as inherent ash and fron 
the enclosing rock strata of the coal bed and so-called "pfurtings" of clay or 
slate within the bed, which is known as extraneous ash. The amount ♦f 
inherent ash is usually fairly constant in the same coal, if of good grade. The 
amount of extraneous ash varies according to the care exercised in mining and 
preparation for market. Ash is the most important constituent to obserte 
in coal, both because of its varying amount and because of the effect of its 
fusibility upon the steaming quality of the coal. 

GUnkers consist of fused ashes, and result from subjecting the ash to a 
higher temperature than its fusing point. Analyses of ash, as ordinarily 
made, are of little value in judging clinkering properties, but it is now possibU 
to determine the actual fusing point and thus select coals of the highest 
fusing temperatures. Ash with fusing temperature above .SSOO degt 
F. seldom forms troublesome clinkers. 

Sulphur most commonly occurs in the form of iron psrrites, either ii 
large, bright, metallic masses or small, brassy scales, With few exceptions^ 
its effect upon the fuel value of coal is negligible, and. while it is customary 14 
give the amount in any analysis, it is of more interest to the mctallurgis| 
than to the marine engineer. 

Caloriilo Value. The heating value of coal is stated in terms of Britisl 
thermal units in America and England, and Calories in most Europeat 
countries. 

Many tables and formulsB have been devised for the calculation of th^ 
calorific value from proximate analyses, but these have proven satisfactory 
only on samples of coals from which the tables or formulse were derived. 

DuLong's Formula, which follows, is accurate within 150 B.t.u. $1 
actual calorimeter test when reliable ultimate analyses are used : , 



B.t.u. per lb. coal » 14,6000 + 62,000 ( H - - ) +4000S, 



(-5) 



where C, H, O and 8 represent the percentages respectively of carbon, hy- 
drogen, oxygen and sulphur found by ultimate analysis. From this formula, 
which is the only recognised standard method of calculation, it is seen thst 
the heating value of coal is derived from the carbon, hydrogen and sulphur, 
notwithstanding the fact that in actual practice these ^ments give up thejr 
heat while in various combinations with each other. The calometric detey^ 
mination of the B.t.u. value of coal should be entrusted only to an experi» 
and if reeults are to prove reliable these tests must be made with proper V 
taken samples, page 247. 

Interpretation of Analyses. Coals are customarily compared kt 
terms of their analsraesi and as there are three general modes of statement 
the analyses must be on the same basis to be comparable. These three modes 
of statement are "As ReceiTed," which shows actual analysis of sampU 
as received at the laboratory; "Dry Coal," which is recalculated from tbi 
actual analysis, eliminating the uncertain moisture element, and "Moisturi 
and Ash Free" (M A AF) erroneously called "combustible basis." Ii 
this last both moisture and ash are recalculated out of the "As Received' 
basis for the purpose of showing the true proportions of volatile matter anc 
fixed carbon, and the heating value per pound thereof. 



CLASSIFICATION OP CQALS 



243 



Table 1. Typical Analsrais of Goal, Illuttrating Iflect of Mode of 

Statement on Same Sample 



As received 



Dry coal 



Moisture aad 
ash free 



Vfoiatur« 

V^olatile Matter 


8.29 

31.19 

49.69 

10.83 

100.00 

2.81 
11.837 


34.01 
54.18 
11.81 
100.00 
3.06 
12.906 


38.56 


Fi»d Carbon 

Ash 


61.44 


Total 


100.80 


Solphur 


3.47 


B.t.u 


14.636 







To ealculate Dry Coal Analyiii from As Received Basis, subtract the percentage of 
moisture from 100.00 and divide the result separately into volatile matter, fixed carbon, 
ash, sulphur and B.t.u. To calculate the Moisture and Ash Free ana^iii from Drv 
Coal Basis, subtract Dry Coal ash from 100.00 and divide the result into each of the 
other Dry Coal items as in the case of calculating Dry Co^ analysis. The Dry Coal 
basis of analysis is the one generally used in engineering. It eliminates all uncertainty 
ooncemina the accuracy of the constantly changing moisture percentage. In any 
luwlysis moisture and ash have the same effect on B.t.u. value when determined by 
calorimeter. These simply act as dilutants of the combustible part of the coal. Start- 
ing with the M. & AF B.t.u. value (sometimes called Pure Coal Value), the addition 
of each per cent of ash or moisture reduces the M & AF B.t.u. value by an equivalent 
percentage. The M & AF B.t.u. value for many coals varies so eKghtly in a large 
series of analyses that for inracticai purpoees an average may be regarded as a standard 
fraxn which to determine approximately the "Dry" and "Aa Received" B.t.u. value 
of other samples in whieh the ash and moisture only are known. The M dc AF basis 
is frequently ci value in identifying coals from analyses which show extraordinary 
peroentasea of m(Hsture and ash. 

ClaMiflcation of Coala. Coals are classified according to both their 
physical and chemical characteristics. No classification based entirely on 
chemical analysee is satisfactory, owing to the overlapping of the various 
elasaes or the gradual merging of one class into the other. The fuel ratio, 
ftied eurbon + volatile matter, is the most common basis of classification. 

Table 1. General Claasiflcation of Coal 



VolatUe 

matter 

per cent 



MA AF 

B.t.u. 



Principal 
characteristic 



AaUiracite 

Semi'-aiitbracite .~ 
Semi-bit u mtnous 

Bituminous 

8iib-bittiminous . 
Lignite 



3to 8 

8 to 12 

15 to 28 

80 to 40 
30 to 46 
40 to 60 



14,500 to 15.000 

15.400 to 15,900 

13.500 to 15.500 
13.000 to 13.500 
11,000 to 13.000 



Hardness and distinc- 
tive analysis 

Low volatile, high 
B.t.u.. friability 

Wide variety 

High moisture, 10-25% 

Brown color, excessive 
moisture. 30-40 % 



llarine CkMli. Semi-bituminoui and bltuminoua are the coali 
beat adapted to marine boileri. Table 3 lists the principal American 
Vunker coals. 

Bemi-bttuminoiu, alao known as "low Tolatile" or ''amokeleM," 
JB a coking coal ot first qoality for marine use. Pocahontas and New River 
brands in this country and Brltiah Admiralty coals of South Wales belong in 
thiM daflB. In addition to it« low volatile and high B.t.u. characteristics, 



244 COAL 

it is usually rather friable or Boft, resulting in considerable slack or fine ooi4 
if much handled. This alack, however, cakes in the furnace. 

Bituminous. This class embraces a wide variety of coals, both ia 
analysis and physical eharacteristios. Owing to the long use of *'bituml- 
nous*' {IS a general name for any coal that was not distinctly anthracite, manfr 
coals are still thus designated which are as distinct in type as the semi- an^ 
sub-bituminous coals which are now separated from the general class. The 
designation may be taken to mean simply high TolfttOe coal. 

8iMS and Grades. Coal as mined consists of a mixture of irregular 
pieces, ranging from large lumps to fine dust. This mixture is known its 
"Run of Mine" and in America is the grade generally used for bunked 
purposes, as it is always in greatest supply at coaling ports. Run of Mint 
is separated into various sizes by passing it over and through screens of 
various meshes. There are no standard screens, consequently sizes vary 
widely in different districts and even in the same district. The most commoti| 
screened sixes, in the order of their relative size, are "Lump," "Egg," "Nut" 
and "Slack." 

At some mines it is the practice to separate the entire output into these sises for con** 
yenienoe in removing impurities, the sises being recombined later into Run of Minci 
This recombined Bun of Mine appears, while still in cars, to be poorly mixed, but th4 
process of unloading into bunkers completes thorough mixing. 

Washed Coal, whether as Run of Mine or screened sizes, is coal from 
which the heavy impurities constituting the extraneous ash have been removed 
in water by taking advantage of the difference in specific gravity of coal 
(about 1.28) and of impurities (from 1.4 to 2.0). The dry coal is fed to tanks; 
called jigs, through which water flows. A strong upward pulsation beind 
given to the water, the good coal floats over the side of the jig and the im^ 
purities gradually work their way against the upward flow of water to th* 
bottom, where they are removed at intervals. < 

Washed Run of Mine and slack, as loaded at the mines, contain a hi^ 
percentage of moisture depending upon the amount of fine coal. This nrit 
only holds large quantities of water but also prevents rapid draining of the eat. 
The lower ash of washed coal more than compensates for its higher moisturi 
as compared with the same unwashed coal in the dry state. 

Impurities in coal comprise "slate," "bone," "sulphur band," pyrite^ 
rock or any other ash forming material which becomes mixed with the co4 
in the process of mining. Of these the most common are slate and bone. 

Slate ia a term widely used to cover most of the foreign material ant 
correctly de»gnates pieces of shale or fire day from the roof or floor of the 
mine or from layers within the coal bed itself, known as partings. Slate oaft 
be easily distinguished by its color and flat shape when black, and is ui> 
mistakable when handled. 

Bone is either smooth, shaley or rough, sandy material containing sufficiedt 
carbonaceous substance to give it the appearance of coal. It ranges from 2$ 
per cent upward in ash. In many coal beds bone has the same fracture as th^ 
associated coal, and is difiicult to distinguish. It usually has a dull lustet 
as compared with its coal, and can be reoogniaed by this or its greatei 
weight. 

Preparation is the process of removing the extraneous impurities from the 
product as it comes from the mines and is being loaded into railroad cars. The 
cleaning and loading plant is called a ti|»|>le, which, at modem operations, is 
equipped with wide conveyors or picking tables over which the coal ia 



RPONTASBOVH COMBUSTION— SiTOrtAaB 245 

Carried in a thin layer toward the loading boomr or chutes to the railroad 
ears. The large pieoes of slate, bone or other impurities are removed by 
hand at the picking tables. Fine impurities can only be removed by washing, 
in whieh case the small sises carrying the impurities are screened out and 
passed through a wmshwy, the larger sises being cleaned by hfind. At 
many of the old operations the impurities are removed in the railroad car, a 
Bmall amount of coal being dumped and raked over at a time. There are no 
standards of preparation other than market demands and competition. 

Selection and Inspection of Coal for Marine TTse. TheobjeotB to be 
g;aiued in selecting a marine coal are (1) Maximum heat value or B.t.u. 
|)6r cubic foot of bunker space, thereby increasing steaming radius or allowing 
more cargo to be oanied; (2) eemi-bituminous or low volatile coal, if obtain- 
able, to minimize soot and tube sweeping; (3) high fusing temperature of 
ash (2450 deg. F. or higher) to reduce clinker troubles and frequent cleaning of 
fires; (4) sufficient lump coal in run of mine to start fires quickly. 

Thcee qualifications must be learned from experience with different coals, although 
the general reputation, description and analysis of a given cual will provide some means 
of judgment. The space required per ton of coal and the analysis can usually be ob- 
tained from the supplier, in which case a comparison under "1." of coals available 
may be made by the following formula: 

^ ^ ^ «. ^ SSM X B.t.u. per lb. of coal 

B.t.u. per cu. ft. Bunker space -  — ^ , 

cu. ft. per ton of coal- 

Coals vary considerable in space i>er ton occupied, ranging from about 40 to over 55 
cubic feet per ton of 2240 lbs., and it is important to take this into consideration when 
comparing B.t.u. values. 

The inspection of a lot of ooal before delivery is made, to the slup is not to 
he wholly relied upon as a means of determining its quality, but is of value 
in comparing different lots of a known coal and in showing in an unknown 
coal whether it (1) contains large pieces of slate or other impurities, (2) is 
eoarse (containing a good percentage of liunps) or is fine (containing much 
slack) (3) is dry or wet. 

* £zi>edenoe has shown that attempted estimates of the percentages of slate, lump and 
water based on visual inspection have proven to be mere guesses, and that the natural 
tendency of inexperienced inspectors is to base their estimates on the sise of the lumps 
and pieces of impurities observable rather than on the amounts. When inspecting ooal 
la railroad ears, it shotUd be borne in mind that the suriaoe of the coal is the only part 
rinble and that it may not represent the entire carload, either with respect to impurities, 
percentage <rf lump or moisture. In a car of run of mine, rain sddom penetrates to a 
greater depth than a few inches, and coal which is dripping wet on top may be perfe<^tly 
dry a foot below the surface. At some mines which make recombined run of mine, the 
arrangement of chutes is such that the coarse ooal goes to the bottom of the car and the 
slack oa top, giving the appearance of slacky coal, while at other operations the reverse 
iB true, while again a good mixture of both may be found. 

The absence of slate or other impurities from the top of a car may not indicate good 
preparation nor is the presence of a few large pieces scattered over the top sufficient 
evidence for condemnation, as both conditions may be purely accidental. The presence 
of impurities all over the suriace jkA a car, however, is sui&eient eridenee of careless 
inreparation to warrant the oonolusion that the sarfaoe indications are representative 
c^ the entire car. 

Bpontaneout Combustion 4nd Storage. The spontaneous combustion 
oi ooal ia caused by the absorption of oxygen from the atmosphere with 
feaultant evolution of heat, which, in a large mass or pile of coal (itself a 
poor heat oonduotor) accumulates until the temperature rises to the ignition 
point* when, if sufficient air circulates through the mass, the pile takes fire. 
The oxidation is greatly accelerated as the temperature rises and it ib believed 



236 



HBAT 



tsrpe* Under favorable oonditions with slightly superheated steam the meat 
value X « 0.923 was found. The corresponding loss of energy is y ^ 0.146 
or 14.8 per cent. With high superheat and a velocity of 2200 ft. per sec., ths 
value X  0.d5 was obtained, but at about 800 ft. per sec. x dropped to about 
0.85. Rosenhain's experiments give values of x for several tyi>e8 df 
nossles. Table 45 gives data and resulte (see Peabody's " Thermodsmamios," 
p. 442). 

Table 46. Values of the Velocity Coeffloient x for Various Types of 

Nossles 

(Rosenhain, Proc. Inat. C £., vol. 140. p. 199) 



Ratio of greatest to 


Taper 


Initial 


Velocity 


Loes of 


least diameter 


preaaure 


coefficient, x 


energy, y 


1.56 


1:20 


150.0 


0.946 


0.105 


1.96 




:I2 


275.0 


• • •  • 


• •  • • 


1.36 




;I2 


97.5 


0.972 


0.045 


1.28 




:I2 


ao.o 


0.903 


0.185 


1.39 




:30 


105.0 


0.913 


0.166 


1.32 




:30 


90.0 


929 


0.137 


1.26 




:30 


77.5 


0.901 


0.188 


1.19 




:30 


62.5 


0.914 


0.165 


1.12 




:30 


50.0 


0.914 


0.165 



Lewioki's experiments on small divergent nossles showed values of i 
lying around 0.955 to 0.96. The loss of energy was therefore 8 to 9 per cent* 

Flow of Steam in Pipes. Since for the relatively short pipes ordinarilf 
used to convey steam the drop in pressure is small, the approximate formula 
p' >" cvo^L/vd is applicable. In the case of saturated steam the product pv'* 
(f' «* specific volume) remains nearly constant for a considerable range of 
pressure. Taking a mean value for thi s product, the equation of flow takes 

the forms p^ » KcM^L/pd^ M ^'Vj/pd*/KcL, Evidence regarding the 
value of the coefficient e is conflicting. The experiments of Eberle indicate 
that c is practically constant for all conditions. On the other hand, experi- 
ments conducted for the Bavarian Revision-Verein seem to show that the 
empirical formulse given by Fritssche for air apply also to saturated and 
superheated steam. In the formula given by Martin, Hawksley, and Hurst, 
e is taken as constant; the formulo of Baboook and Unwin make e vary with 
the diam. of pipe according to the law c « K[l + (S,0/d)], with d in inches. 
A comparison of different formula is made by Professor Gebhardt in Power, 
June, 1907. See also Lucke's '* Engineering Thermodynamics," p. 1117.^ 

Eberle'e value of the coefficient c is 2.225 X 10"* with d in ft. and 2.667 X 
10"* with din in. The formula used by Martin and others is p' = KM^L/Dd^, 
and with M in lb. per min. and d in in., k has the following values: Martin, 
0.0003133; Hawksley, 0.0003370; Hurst. 0.0003126. 

Baboock's formula is p' -> ib [1 + (3.6/(f)](Af >L/D<f>), with i^ » 0.0001321 
(Af in lb. per min. and d in in.). 

As an example, take saturated steam at a pressure of 80 lb. per bq. in. flowinsin a 
xoain 500 ft. long and in. in diam. Under these conditions T/pw ^ 0.129, and from 
the table of ooeffioients e * 1.69 X 10"*. The specific volume is 5.47 ou. ft. per lb. 
and D « 0.1829 lb. per ou. ft. M ^ 2.7 lb. per sec « 162 lb. per min. 

By Babcock's formula, p' « 1.96 lb.; by Eberle's p' - 2.28 lb., and by Martin's 
formula, p' - 2.89 lb. 



THROTTLING 237 



ThrottliniT 

Throttlinff or Wln-drswinf . When a fluid flows from a region of higher 
pressure into a region of lower pressure through a valve or constricted passage, 
it is said to be throttled or wire-drawn. Examples are seen in the passage 
of steam through pressure-reducing valves, in the flow through ports and pas- 
sages in the steam envine, and in the expansion valve of the refrigerating 
machine. 

The gMDtral •quatlon applieable to throttling prooMMS is derived 
from the general equation for the flow of fluids, namely. 

The velocities tDi and 101 are practically equal, and it follows that ix » ts; 
that is, in a throttling process the initial and final values of the heat content 
are equaL 

For a mizture of liquid and vapor, t m »' 4- xr, hence the equation of 
throttling is i'l + ^n "■ i'f\r xtffe In the case of a perfect gas,«  CpT + i«, 
hence the equation of throttling is CpTi + Co » CpTt + to* or Ti >■ 7*i* 

Joule-Thomion lilect. The investigations of Joule and Lord Kelvin 
showed that an actual gas experiences a drop in temperature when throttled. 
The ratio of the observed drop in temperature to the drop in pressure, that is» 
dT/dp, 18 the Joule-Thomgon coeflicient. According to these investiga- 
tors, tiiis coefficient varies inversely as the square of the absolute tempera- 
ture, but is independent of the pressure. More recent experiments indicate* 
however, that the coefficient also varies with the pressure. 

The cooling eileet produced by throttling has been applied by linde 
to the liquefaction of gases. 

Loss Duo to Throttling. A throttling process in a cycle of operations 
always introduces a loss of efficiency. If 7*o is the temperature corresponding 
to the back pressure, the loss of available energy is the product of To and the 
increase of entropy during the throttling process. The following example 
illustrates the calctilation in the case of ammonia passing through the ezpan- 
oon valve of a refrigerating machine. 

Bxample. The liquid ammonia at a temperature of 70 deg. fahr. passes through the 
valve into the brine ooil in whioh the temperature is 20 deg. and the pressure is 47.75 lb. 
per sq. in. The initial heat content of the liquid ammonia is t'l  42.1, and therefore 
the final heat content is t'l + »trs - — 12.6 + 5.56.3a:» «» 42.1, whence «■ - (42.1 + 
12.6)/656.3 - 0.0085. The initial entropy is «'i » 0.0813. The final entropy is 
•'i + (*ir«/rt) - - 0.0262 + 0.0986 X 1.1599 - 0.0880. T. - 20 + 460 - 480; 
hence the loss of refrigerating effect is 480 X (0.0880 ~ 0.0813) « 3.2 B.t.u. 



SECTION 3 



FUELS AND COMBUSTION 
I FUEL OIL BURNING 

I BY 

JOHN 8HOBBB BUBBOWS, Consulting Engineer for Castner, Curran A 
Bullitt; Mem. U. 8. Fuel Administration, U. S. Geological Survey, 
U. S. Government Goal Testing Plant; Mem., A.S.T.M., Inter. 
Ky. Fuel Assn. 
! FBANK WARD STBBLINQ, Lieutenant Commander, U. S. Navy, Design 
Division, Bureau of Steam Engineering, Navy Department; Sec'y 
Treas. A.S.N. E.; Mem. Soc. Nav. Arch. & Mar. Eng. 

M. PSNH, Lieutenant Commander U. S. Navy. In Charge of 
Navy Fuel Oil Testing Plant; Mem. A.S.N.E. 



CONTENTS 



OOAL 

By J. S. BURROWS 



Paob 



Composition 241 

Analysis 241-243 

Claasification 243 

Marine Coals 243 

Selection and Inspection of Coal for 

Marine Use 245 

Spontaneous Combustion and Stor- 
age 245 

t- S. Navy Coal.^ 246 

Standard Steaming 247 

Sampling 247 

OIL FT7XL 

By F. W. sterling 

Petroleum and Fuel Oil 250 

Properties of Petroleum 251 

Coets, Coal and Oil Fuel 252 

Oil Fueling Stations 253 

Advantages, Coal and Oil Fuel 254 

Physical Properties 256 

HRating Value 256 

Viscosity 256 

\l8cosity Conversion Curves 260 

Specific Gravity 262 

Bxpansion 262 

Sipecific Heat 267 

Plash Point 268 

Fire Point 269 

Centrifuge 271 

Conservation 273 



Sleety Precautions: 

Burning 

Carrying 

Loading 



Page 

274 
275 
276 



COMMERCIAL QASOLINB 

By F. W. sterling 

Properties 

Specifications 

Tests 

COMBT78TION 

By F. W. sterling 

Air Required for 

Excess Air 

Volume Contraction 

Combustion Products 

OIL FXTBL BXTBNINa 
By albert M. PENN 

Atomisation and Atomizers 

Air for Combustion 

Air Registers 

Boiler Furnace Design 

Furnace Insulation 

Relations Between Rate of Com- 
bustion, Heating Surface, Furnace 
Volume and Air Pressure 

Fuel Oil Equipment 

Boiler Room Instruments 

Operation 

Precautions 



277 
277 
278 



279 
2S0 
280 
280 



281 
287 
292 
297 
297 



299 
301 
315 
322 
326 



I 

f 



239 



OIL FUEL* 

BT 

FRANK W. STERLraO 



Petroleum, wbioh is a variety of 
oombinations of hydrocarbons of the 
paraffin, napthene and olefin series, is, 
because of its abundance and cheapness, 
the commercial source of all marine oil 
fuel. Bhale, tar and creosote oils are 
not considered in this field to-day be- 
cause of their greater value for other 
purposes. 

There are three kinds of petroleums in 
use, namely, the so-called paraffin base, 
the semi-paraffin base, and the asphaltio 
base. To the first group belong the oils 
of the Appalachian field, comprising 
Pennsylvania, eouthem New York, 
West Virginia and eastern Ohio. To 
the second group belong the oils found 
in the Middle West, such as the Illinois, 
Kansas, and Oklahoma fields. To the 
third group belong the oils found on 
the Gulf Coast in Texas and Louisiana, 
in California and in Mexico. 

The first tw.o groups obtain their name 
from the fact that they contain paraffin wax 
and amorphous waxes such as petrolatum. 
The third group obtains its name from the 
fact that on distillation a residue of asphalt 
is left in the still. Table 1 shows the world's 
total marketed production of crude pe- 
troleum. Composition and calorific values 
of various petroleums are given in Table 2. 

Fuel oil may be classed as topped 
I>etroleum, that is the residue after the 
more valuable and volatile constituents 
have been removed by distUlation leaving 
a heavier and safer oil for burning 
purposes. Upon distillation, i>etroleum 
gives oCF in the order named, gasoline, 
kerosene and lubricating oils. The 
residue is fuel oil 

Fuel oil, from the standpoint of the pe- 
troleum trade, generally includes all oils 
which are burned under boilers. Special 
distillates sold as Diesel Oils come under this 
head. Until 1914 much of the California 
crude oil was sold as fuel <m1. The rapidly 
increasing value of the lighter distillates has 
caused the abandonment of this practice. 

* In preparing the data for this section the 
writer has drawn freely on a paper, Oil Fud, 
presented by Mr. BmeM H. Peabody before 
the Intematumal Bngxn^ering Congre»»t San 
Francisco, Cal. 

250 



I 

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PROPERTIES or PSTROLBUU 



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The leMt valuable products of distillation, to- 
gether with Bome residuuin, constitute the fuel 
oil of to-day. The distillates of such low value 
as to be sold tor fuel oil are usually the products 
distilling ofiF after kerosene, and those too heavy 
for burning in lamps and too thin to be used as 
lubricating oil. 

About S/S of tho world's produetion of 
petroleum may bo eonildered fuel oil. 

Stor&g^ Mid Distrlbutinff Stationg. 

Tho stations on the following pages, in the 
United States and Canada, are equipped 
with ample pumping capacities and pipe- 
line facilities for unloading tankers, loading 
tanks, cars, and fueling vessels. Table 3. 

ReUtive CoBts, Coal and Oil ruolt. 

The fuel cost of producing steam with oil 
and coal are the same when cost of coal 
in dollars per long ton — 1.907 X cost of 
oil in cents per gallon; or, as Afr. Waiter 
M. McFarland first pointed out, when the 
cost of coal in dollars per long ton is 
double the cost of oil in cents per gal.» 
the fuel cost of producing steam will 
be approximately equal. This assumes 
equal boiler capacity with oil and coal 
and that boiler efficiencies of oil and coal 
are as 75 to 68, and further assumes coal 
of 14,400 B.t.u. per lb. and oil of 18,600 
B.t.u. pet lb. with a weight of 7.88 lbs. 
per gal. (18^ Baum6). In round numbers^ 
OS steam producers 1 lb. oil — 1^ lbs. 
coal, or 4H b^l* oil « 1 ton coal. 

Fig. 1, charts A to D, from data by C. C. 
Moore A Co., furnish a rsady method of 
comparing fuel costs for oil and coal. Charts 
B tku D are constructed for 13,800 B.t.u. coal 
and 18,500 B.t.u. oil. Charts A and C are used 
for coala and oils of other heating values. 

Assuming a coal costing $4.50 a ton. with a 
value of 13,800 B.t.u. and giying a boiler 
efficiency of 65 per cent, if the efficiency obtain- 
able with an oil of 18,500 B.t.u. heat value is not 
known, it can nfely be .assumed that the net 
effidenoy will be 4 per cent greater, or 60 per 
cent. On chart B follow the horisontal for 65 
per cent efficiency with coal to the diagonal of 
60 per cent net efficiency with oil (using the 
upper row of figures). 4.3 barrels of this oil is 
found to be equivalent to a ton of coal. On 
chart D follow the vertical for 4.3 barrels till it 
meets the $4.50 fine for coal. The equivalent 
price for oil will then be $1.04 per barrel. If oil 
could' be purchased for anything less than this, 
the fuel expense would be decreased by changing 
over. 



FUBLING STATIONS 



253 



Tftbto S. Fartial LUt of Oil Diitribiitinff Stations in the United 

States (Peobody) 



Place 

Aberdeen, Wash. 
Alameda Pt.. Cal. 
Aransas Pass, Tex, 
Aatoria, Ore. 
Avon, Cal. 
Baltimore, Md. 
Baltimore, Md. 
Baltimore, Md. 
Baton Rouge, La. 
Bi^onne, N. J. 

(N. Y. Harbor) 
Bayonne, N. J. 
BeUinsham, Wash. 
Boston, Mass. 
Boston. Mass. 
Boston, Mass. 

Carteret, N. J. (Near N. Y.) 
Chester, Pa. 
Charleston, S. C. 
Charleston, S. C. 
Charleston. S. C. 
Cristobal, Pan. 
EI Segundo. Cal. 
Eureka. Cal. 
Galveston, Texas 
Gaviota, Cal. 
Guantanamo Bay, Cuba 
Honolulu, H. I. 
Honolulu, H. I. 
Jacksonville, Fla. 
Jacksonville, Fla. 
Ketchikan, Alaska 
Key West, Fla. 
Key West, Fla. 
Lhmton, Ore. 

(Near Portland) 
Marcus Hook, Del. 
Mare Island, Cal. 
Melville Station. R. I. 
Mobile, Ala. 
Monterey, Cal. 
Morgan City, La# 
New Orleans, La. 
New Orleans, La. 
New York, N. Y. 
New York, N. Y. 
Norfolk. Va. 
Norfolk, Va. 
Oakland, CaL 
Panama 

Pearl Harbor, Hawaii 
PfaOadelpfaia, Pa. 
Point Breese, Pa. 
Point Wells. Wash. 

(Near Seattle) 



Oil Company 

Standard Oil Co. of Cal. 
Associated Oil Co . . . 
The Texas Company 
Standard Oil Co. of Cal. 
Associated Oil Co . . . 
Interocean Oil Co . . . 
Standard Oil Co. of N. J 
The Texas Company 
Stondard Oil Co. of La. 
Standard Oil Co. of N. J 

The Texas Company . 
SUndard Oil Co. of Cal. 
Mexican Petroleum Co. 
Standard Oil Co. of N. Y 
United States Navy 
Interocean Oil Co . . . 
Interocean Oil Co . . . 
Standard Oil Co. of N. J. 
The Texas Company 
United Stotes Navy . . 
The Texas Company . 
SUndard OU Co. of Cal. 
Stondard Oil Co. of Cal. 
The Texas Company . 
Associated Oil Co.. . . 
United States Navy . . 
Associated Oil Co. . . . 
Stondard Oil Co. of CaL 
Standard Oil Co. of Ky. 
The Texas Company . 
Standard Oil Co. of Cal. 
Standard Oil Co. of Ky. 
United States Navy. . 
Associated OU 0> . . . 



Sun Oil Co 

United States Navy . . 
United States Navy . . 
The Texas Company . 
Associated Oil Co . . . 
The Texas Company 
Mexican Petroleum Co. 
The Texas Company . 
Mexican Petroleum Co. 
Standard Oil Co. of N. Y 
The Texas Company 
United Stotes Navy . . 
Standard Oil Co. of Cal. 
Mexican Petroleum Co. 
United States Navy . . 
The Texas Company . . 
Atlantic Refining Co. . 
StoBdard Oil Co. of Cal. 



Storage 

Capacity 

Bbl. of 

42 Gal. 

34,0(X> 
37,500 
65,000 
10.000 
1,000.000 
220.000 
50.000 
55,000 

300,000 

276.000 

8.500 

200.000 

50.000 

50.000 

100.000 

120,000 

15.000 

104.000 

35.000 

110.000 

100.000 

35,000 

110,000 

120.000 

212,000 

102.000 

100.000 

50.000 

55.000 

38,000 

50.000 

35,000 

173,000 

600,000 
100,000 

85,000 

25.000 
340,000 

66,000 
400,000 
124,000 
500.000 
100.000 
138,000 
185,000 

10,000 
100,000 
235.000 
334,000 
500,000 
200.000 



254 



OIL FUEL 



Table 3. Partial List of Oil DUtaribisting Btations in the UniUd 

States (Peabody) — Continued 







Storage 






Capacity 


Place 


Oil Company 


Bbl. of 
42 Gal. 


Port Arthur, Texas 


The Texas Company . 


. . . Practically 
unlimited 


Port Chalmette, La. 


Standard Oil Co. of La. 




Port Coeta. Cal. 


Associated Oil Co . . . 


. . . 480.000 


(Carquines Strait) 






Portland, Me. 


Mexican Petroleum Co. 


. . 200,000 


Portland, Mc. 


Standard OU Co. of N. Y 


. . . 80,000 


Portland, Ore. 


Standard Oil Co. of Cal. 


. . 85.000 


Port Townaend, Wash. 


Standard Oil Co. of Cal. 


. . 27.000 


Providence, R. I. 


Mexican Petroleum Co. . 


. . 100.000 


Providence, R. I. 


Standard OU Co. of N. Y 


. . . 10.000 


Providence, R. I. 


The Texas Company . . 


. . 253,000 


Puget Sound, Wash. 


United SUtes Navy . . 


. . 100,000 


Richmond, Cal. 


Standard Oil Co. of Cal. . 


. . 200.000 


Sacramento, Cal. 


Associated Oil Co 


. . 5,100 


Sabine Pass, Texas 


Sun Oil Company . . . 


. . 250,000 


San Diego, Cal. 


Standard Oil Co. of Cal. . 


. . 34,000 


San Diego, Cal. 


United States Navy . . 


. . 100.000 


San Francisco, Cal. 


Associated Oil Co 


. . 97.800 


San Francisco, Cal. 


Standard Oil Co. of Cal. . 


. . 15,000 


San Pedro. Cal. 


Standard Oil Co. of Cal. . 


. . 35,000 


Seattle, Wash. 


Standard Oil Co. of Cal. . 


. . 90.000 


Stockton. Cal. 


Associated Oil Co . . . . 


. . 5,200 


Tacoma, Wash. 


Standard Oil Co. of Cal. . 


. . 34,000 


Tampa, Fla. 


Standard Oil Co. of Ky. . 


. . 70.000 


Fuel Oil Distribution Stations of the Imperial Oil Co 


mpany. Limited 


Fort William, Ontario 


Prince Rupert. B. C. Toroi 


Bto, Ontario. 


Halifax, N. S. 


Quebec, Quebec. Vancouver, B. C. 


Montreal, Quebec. 


Barnia, Ontario. Victo 


ria. B. C. 



Assume a ooal of 14,400 B.t.u. giving an efficiency of 70 per cent, and an oil having a 
heat value of 6,323,000 B.t.u. per barrel. On chart A follow the vertical corresponding 
to 70 per cent efficiency for coal till it intersects the diagonal of 14,400 B.t.u. for ooal. Tho 
intersection comes on the horisontal for 73 per cent, which is the equivalent efficiency 
of coal of 13,800 B.t.u. Use this on chart B as before, assuming 4 per cent, greater net 
efficiency with oil. 4.33 barrels of oil of 18.500 B.t.u. per lb., or 6.216.000 B.t.u. per 
barrel are found to be equivalent to one ton of coal. On chart C follow the vertical for' 
4.33 barrels to the diagonal for oil of 6,323,000 B.t.u. per barrel, obtaining 4.25 barrels of 
oil equivalent to one ton of the given coal. From chart D, using the vertical for 4.26 
barrels, as the coal costs $4.50 per ton. $1.06 per barrel would be equivalent for the given 
oil. 

Relative Advantages of Oil Puel and Coal. The advantages of oil 
fuel are (1) reduced handling costs and ash handling eliminated, (2) reduced 
Ubor in the firerooms, (3) increased life of boiler and reduced maintenance 
costs in all departments, (4) increased steaming radius for same bunker 
capacity, or, for same cruising radius, saving in dead weight or cargo space, 
(5) increased efficiency and capacity, due to more constant furnace tempera- 
ture and cleaner tubes, (6) time saved on voyage due to steadier steaming 
and shorter fueling time, (7) fueling at seaeimplified (military), <8) smokeless 



COST OF OIL VS. COAL 25S 

•Manins poadhle (military), and (S) maumum rate of oombUstioik can bo 
Mtauied inatantly (oulitary). Against these advantagea miut be obaried 
the higher fint ooot of instaUation for oil buroiDg. 



(CvuTifty of Harriaon 



It hu bccD eoBservatirciT ntimaltil tbst tha »vini 
OTR cod burnjiic in m 3S0D I. H. P. v««l i« eqiu] to 01 
of flnt coatA ni iiutiiUation«. 



256 



OIL FUEL 



PhysiOAl PropertiM. The claasifioations of oils according to their 
density is very commonly used to denote other characteristics. Thus a 
heavy oil is usually expected to be viscous and sluggish with a high per-* 
centage of asphalt and comparatively low heat value on a weight basis, 
while a light oil is supposed to be very fluid at ordinary temperatures, very 
volatile and rich in the lighter hydrocarbons and high heat value on a weight 
basis. While in general, these characteristics hold true enough to explain 
the prevalent association of ideas, so many exceptions and variations occuf 
that is it essential to clearly specify the various properties of a particular oil it 
order to Identify it. Density is not a measure of- volatility, nor does weight 
determine viscosity. The early theory that the density of oil was related 
to the depth of the oil well has not been borne out in later exploration. 

Heating Value. The ultimate analysis of crude oil (petroleum) gives a 
composition of carbon, hydrogen, sulphur, oxygen and nitrogen. The H 
and C contents usually vary within the limits of 11 to 14 per cent and 87 to 84 
per cent respectively the amounts of O, N, and S, being very small. Table 2. 

The heat value of oil is usually given as the high heat value, as determined 
by the bomb calorimeter. The actual or low heat value available 
for furnace use is less than this because heat of the vapor formed by combus- 
tion of H in the oil passes up the stack as waste heat. Af . IncKUy'B empirical 
formula for the higher heat value, based on ultimate analysis, is B.t.u. per 
lb. "- 18,500 C + 60,890 H. The heat value may also be roughly estimated 
by Sherman and Kroff^a formula based on density, as follows: B.t.u. per lb. 
° 18,860 X 40 (Bauma - 10). 

The heat value of fuel oil varies between about 16,000 and 20,000 B.t.u. 
per lb., 18,000 to 10,000 being the common values. Table 4 was prepared 
from the files of The Babcock & Wilcox Company: 

Table 4. Heat Value of Fuel Oila 

Specific B.t.u 

Sooroe gravity per lb. Authority 

California. Coalings Field 0.927 17,117 Bashore 

BakerB6eld Field . 0.992 lg,267 Wade 

Kern River Field 0.9fi0 18.845 Bashore 

Loe Anseles Field 0.977 18,280 Bashore 

Monte Cristo Field 0.966 18,878 Bashore 

Whittin Field 0.936 18,240 Wade 

Texas. Beaumont 0.924 19.060 U. S. Navy 

0.903 19,349 Bashore 

Sabine 0.937 18.662 Bashore 

Pennsylvania 0.886 19,210 Booth 

Mexico 0.921 18.840 Bashore 

0.981 17,551 Bashore 

Viacoaity may be defined as the resistance to internal movement, or the 
Intemibl friction of a liquid. It may Ije measured by observation of the 
ability of the liquid to oppose the movement of a body through it, or more 
commonly by noting the time required for a definite quantity of the liquid 
to pass through an orifice or short pipe under known conditions of tempera- 
ture and head. In atatinir Tiscoaity the name of the instrument 
used must be given, also the temperature at which it was run. 

Absolute Visoosity may be defined as the force in dynes required to move a layer of the 
liquid of 1 sq. cm. area over another layer of the liquid with a velocity of I cm. per seo. 
It has not been found practical to actually measure viscosity by sliding plane surfaces 



ant tamb otber. Tb* moat »eoimte n«thod deTslopad ■• that ol obaerYlD« ali 
ol tbn liquid throuch sapUlarj tiib«(, PoUMUllla'i [<mnulK, in which th; v: 
ii upRMaed u  funrtian of tba appliKl pKHure snd the quaotity dischirged, i 
on invealicBtiona oF Mpilluy Sow; it ia, 

A. T. - ^t, wbara A. V. - abwilub 
em., r • ndiiia of eapUlwy 
tabe in cm.. I - Icnclh ol 
tub* in cm., >- ioIbdkoI 
bquid pa>iri tfarouf b tfa« 



iniaht ba aallad " tpadflo 



With the advent o( 
the viwua crude oils £ 
of Mexico and lh« in- ° 
rasaBed Use of beavy ' 
dintillatee from other 
fields, coupled with the 
wide adoption of the 




or prsuura bumv, 
the degree of viacoidty 
of oil beoomee a matter 
of the utmost import- 
ance. Most viscous oil 
muat be heated before 
pumpiiis- Aud the vi»' 
cosily must be reduoed 
before it can be used 
iu the burner; in fact, 
the whole problem of 
handling vueoua oiU 
really hinitee on via- 
floeity, see p, 286. 

Tliao«lm*t*r>. 
Delemunatlon of vls- 
coeity by capillary 
lubes ia the most accurate tli«Uiod aa yet evolved. However, it iaeaaentially 
a laboratory method, the apparatus iDv.ilved is too delicate and complicated 
and the time required too long for comnieri^ioi application. 

In tbe Mnmnarolal tlKoaimelerB, such aa the Enoler, Rtdtcood. and 
SayboU, a anuUl quaotity of the liquid is permitted ti) flow through a cylindiicnl 
or ooniuBl openine that is short and relatively large in diameter IH to H 
in. long, approximately 0.01 in. diam.). The time of efflux of a given quanUty 
is taken as indicating the viscosity. The accuracy of the capillary tube is 
BBcrificed to obtala ruggedneaB and comoMrdal rapidity. Flow through 

17 



— Engh 



258  OIL FUEL 

short dioohargee a so rapid that turbuleooe and eddies with the Ught«r 
liquids caiue nearly aa much resistance as the actual viscosity of the flujd. 
For idcDtifying a liquid by eompanion wi(h a etanilftfd liquid tbe eommercitl via- 
eodmfften an Batisfaotoryr even though tLj«y nay not indicht« the IfuQ viocowty. For 
aoeurate itudy of th« flow at liquids they oannot be relied upon. 

Tha Xaciar TiaeoiiiiuteT. FSi. 2, ii Bpecified for C. S. Navy fuel oil tota. It 
coDBita of an oil chamber a, with platiuum tube outlet c, ■urrounded by water bath b. 
For lu(h tamperalu™ an ati bath is UKd. The platinum outlet is 20 mm. loua. with 
a bwe of 3.6 mm. diam. at top and a.S mm. al bollotn. A volumB cf 200 t.e. o( the 
oil to be teaMd 1* allowed to flow out and Che time it noted in Koonda. The number nf 
■eoOBdl required for 300 c.c. water to flow out at the temperature of 20 deg. C. (08 dec. 
F.) ii then determined (SO to &2hc. in theatandaRliuitrumenll, Vigcoaity ialound by 
dividiac the lime raquired for the outflow of oil by the time of outflow of waCtc, 

Tba Barbolt Uufrarsal Vlaaoal- 
nMtar, Flc. 3. ii ipecified for U. & 
Navy fad oil tots when the Enilv Op 
iutruinent ia not available. It ii the 
m«t popular of the viaooaimetera 

for lubrieatinc oil testins. It is , 

made eDtirely oC melaL The oytinder 
C which hdda S3 c.c. of oil. ia sur- 
rounded by a larce batb B. The 
upper edce of the cylinder ia Bur- 
rounded by a (allery G, into which 
any aurplua oil flowa. At Ih? bottom 
of the cylindnr ia a jet J, through 
whiah tiie oil flowa into the teeeivinc 
flaak F, which holda 00 c, o, to • mark 
on its Dsck. The let ia encloaed by 
the tube T, which eitenda below the 
orifiee of the jet. and into the bottom 
of which a corli L with a atrinc 
attached i* lichtly inaerted. ao as to 
oloae the lube. The bath la provided 

with stirms, 5. and fitted with  _ , _ , , 

tharmomater. for keepins the tem- '™' 3. — Sayboit Universal. Tucoaimeler. 
pcrature uniform. The bath ia tkeated 

by a fas rinc hunter R. which exteada around in a circle under the bath, or by a 
' ateam U-tube or by an eleotric attachment. 

To make the teat, Bll mi cylinder with oil to be teated, and fill bath with oil or water 
of the requited temperature. The ral temperature is t^ulated by the bath temperature, 
(he dl thermometer beini used to atu- the oU. When the oil ia at the correct temperature, 
tlie bath temperature beiae; a trifle higheri the thermometer b withdrawn and the gaK 
lery ia emptied of all aurpliu oil by meani of a pipette. The oil now eioetly filla the 
cylinder. Flow ol oil "ia started hy quickly pulling atrinc which withdraws cork L. 
Time ol outflow of 60 c.c. of oil indicatee the Tiicoaity. Sayboit TisooaimBUre an go 
■taudardiaed that viaotiaity of water ia 30 with thia inatrument. 

The EedVOOd Tlsooalnwtsr, Fig. 4. oon«iat< uf a lilvered.oopper oil cylinder A, 
m ia. diam. and 3H in. Ions, fitted with an a<ate outlet jcL The cylinder is fined in 
a ooHier wat«r or oil hath C which ia fitted with a hcalinEtubef proiecting down at an 
ancle of 4G dec- A is an wtator, T and Ts aze thermometi'ra for bath and oil cylindere 
rcapectirely. The oil cylinder atopper conaiata of a amall briua ephere which rata in a 
bemiipherical cavity in the a«aU jet. A is an adjuatable Eauge to indiente the Rllinc 
height of cyhnda. 

To make the test, fill bath with auitabh) Uquld (water for temperatures to 100 de>. F. 
and mineral all above that range) to a height corresponding to that of the gauge. 
When bath ia at the required temjjerature the oil to be teMed ia poured into the cylinder 
until ita level juat reaehea the gauge point. A gas flame may b« applied to the healing 
tube to brlna nil to the teat temperature. WbsD at thia temperature the Itall valve is 



rsind by the trir' V and the time of DulHow ol 50 r.e. oF dl la noted. Tbr viMnlty - 
(FXlOOXO + CSSSXO.eiG). where P-tbe Dumbfr of kc. o( outBoir of SO o.e. of oil 
aod <7i> the (pacific snvity of the oil uiidv teat. It takaa &3£ ho. loi 50 b^o, of npeceed 



. On'oK CKk 



f°- h 




oil Bt flO des- f. to So* oat M standard oondltloni and O.SIG l> the sp. fr. «1 niw oil at 
60 dec. F. The time of outBon of aO e.e. d( water at 00 def. F, it 2fi.G ten. 

In the orisilial itandatdiiing of the inatrument , tlieht daparturea from the etandanl 
nae ol the oriflae may be cometed br ptachia the lance-poiBt  little hlgluv or towei. 
If. howevai, there be any ODDeiderable daviatioo (rom tlie model, especially in regpMt 



260 



OIL FUSL 



/ 











7 




1 










1 










1 





600 




1 






/ 




/ 




























c\ 




/ 




/ 




































/ 




/ 






























^ 400 






( 


p/ 




/ 






























8 








/ 




f 


















^ 












1 






I 
1 ■^ 


f/ 


















/ 


r 












1 300 
























/ 




^ 


















i 










• 


^ 




y 
















Si 






// 












L> 


'^ 


















£aoo 






' 










^ 


/ 


CL 




























J^ 


t^ 




























' 








y 


w^ 












d^ 




■^ 


■^ 










100 


J 


u 




^ 


/' 




























» 


1 


t 


^ 


J^ 






^ 








 






















^ 


^ 


"^ 


































n 









































2 4 e 8 10 12U16182022242628a08234868840 

Bnirler Viscosities 
Fio. 6. — Engler-Saybolt viscsomty oonvenion curveB. 

























f 






• 














400 
















. 




/ 






































t 


/ 








































/ 








































y 


f 
























|800 
















/ 






































/ 
















/ 












o 












b 


/ 














/ 


^^— 












? 












/ 












>< 


/ 
















1 200 










/ 


f 










y 


/^ 


























/ 










/ 


K 





























J 


f 






a 


/ 
































/ 


. 




V 


/ 


























100 






J 






y 


iT 
































/ 




/ 


^ 


































/ 


A 


/ 






































/ 

* 


/ 


i 


































A 










































1 


D 




1( 


)0 




a 


X) 




a 


90 




4( 


)0 




5( 


K) 




e( 


)0 





RedwQod Viscosities 
Fw. 6. — Redwood-Saybolt Tl0OO8ity ooaTenioo ourvM. 



VISCOSITY 261 

of lit* Iwicht ol the aolDmB of oil. tlw inatru 

naulU u the ptttecD with s certiua oil. I 
rvsulla with Lnothar oil of differefit visconty 

Tha AdmlnJtj Typ* Bvdwood Tlieorimrtw, i modiScmtioii c4 tbe iboTB^ n ths 
Encliflh Btvliifcrd for oil fueL It h*« b«vn BpediUly d«ugiied for fiul tai wotk ukd ic 
iDtended lor UH ftt 32 dft. F. The oil-v«Hl is □( the ume dimensioni h that ol the 
oriffua] iofltrumvnl, but th« aftale j«t u longer, nod of larger bore, thia vUcomctei b«iikB 
diVKiiDd to ijve aa outflow !n one-tenth of tha tlm« occupied in the outflow of a aimilar 
Tolume flora the original pattern. The jet is bo monnlBd aa to be eomplelely lurrouaded 

■a imnlaiteii, haa no latent baBtim-tube. bat ia pmvidad with tha uaual [otaling atimr. 
Oil to be teated ihauld beaubieoted to prolonssd ooolinc at 33 dag. F„ by baing kept ina 
nfriEcrator through the night, or for at leaat aii hour*, immcdialely before beinx placed 
in the oil-cup, aa[l ahould be thoroughly atin^ belorc being tranaferred. When aceu- 
rate teaulta are deaired. the vtacometer ahould be placed in a refrigerating ohaoiber, the 
tcmpersture ol whieh la maintained at 32 det. F. 



CODfOTlion of VtaoodtT 8e»teg. An einct relation between the difTereDl 
TMoooity scales does not exist: it varies with different liquids, eaperialiy 
BO with diflFerent oils, for the reasons above mentioiied. Under the majority 
ol working oonditioDa. the error is only a few per cent. For practical purposes 
the curves given in Fi^. 5. 6 and 7 are sufficiently accurate. 

To Canrert to Absolnta Vlieaiity by Fii. 7, which curvea were publiahed in Stand- 
•fd Oil Bulletin by Standard Oil Co. ol California^ AHume an oil which at TO de(. F. 
tws  TiaoOBtj of 2300 Saybolt seoonda and • density of 0.95. Fcdlow dotted line rerti- 



262 OIL FUEL 

eaXty from 2800 up to curve mArked, *'9aybolt Universal, thence horixontally to the left. 
"n/(f" for this oil is 4.2; since "d" the density of the oil at 70 deg. F. is 0.95, its absolute 
viscosity "n" is 0.96 X 4.2 ^ 4.0. 

Speoifle GraTity. The ease with which the density of oils lighter than 
water is determined by reading the scale of a Baum6 hydrometer immersed 
in the liquid has resulted in the general adoption of this method,. In tables 
of sp. gr. it is usual to show the temperatures, thus sp. gr. at 60^/60® F. indi- 
cates the sp. gr. of the oil at 00 deg. F. is referred to water at 60 deg. F. as 
unity. In the evolution of marking the Baum6 scale, various makers deviated 
from time to time until the scale became eomewhat confused. Ail Baum6 
scales in use to-day are based on an assumed relation between the Baum6 
scale and the sp. gr. scale at the same temperature. 

The XT. 8. Bureau of Standards has determined that, for liquids lighter 
than water, the true relation between the Baum6 gravity and the^p. gr. is 
expressed by the formula: sp. gr. at 60^/60^ F. -> 140 -i- (ISO+^B); and for 
liquids h#aTier than water by the formula, sp. gr. at W^/W* F. "146-i- 
(145 - B). 

The readings on the Tagliabue hydrometer, which is a Baum6 scale 
much used in the oil industry, may be converted to sp. gr. by the formula: 
sp. gr. at 60^/60'' F. - 141.C -^(181.6+8). 

For heavy viscous oils the use of the hydrometer is a slow process and one liable to 
considerable error. Such oils may be heated to make the use of the hydrometer feasible, 
due correction being made for temperatiu^. Oils as heavy as water are already used 
as f ueb. The specific gravity scale is used where extreme accuracy is desired as in 
computations. Tables 5, 6 and 7 were abstracted from Bureau of Standard* Circular 
No. 67. 

Ooeffieient <rf Kxpansion. Oil is sold in the United States by volume, 
not by weight, therefore the temperature at which it is measured must be 
given; 60 deg. F. is standard in this country. Table 8, abstracted from 
Bureau of Standards Circular No. 57, furnishes a ready method for converts 
ing a measured volume at other than standard temperature to equivalent 
volume at 60 deg. F. This table is based on the fact that within the limits 
of ordinary measurements the rate of change of specific gravity with change 
of temperature is the same for all oils of the same speciiElc gravity. 



SPSCJFIC ORAVTTY 



263 



Tabto 8. DegreM Bftum6 and OorrMponding^ 8p. Or. of Oil, Lb«. p«r 

- Oal., and (HA. p«r Lb. 



Degroea 
BaumA 


Specifio 
gravity at 
60VWF. 


Pounds 

per 
gallon 


Gallons i 

per 
pound 


Degrees 
BanmA 


Specific 
gravity at 

So»/e<y»F. 


Pounds 

per 
gallon 


Gallons 

per 
pound 


10.0 


1.0000 


8.328 


0.1201 


28.0 


0.8861 


7.378 


0.1355 


10.3 


0.9964 


8.299 


0.1205 


28.5 


0.8833 


7.355 


0.1360 


11.0 


0.9929 


8.269 


0.1209 


29.0 


0.8805 


7.332 


Ovl364 


11.5 


0.9094 


8.240 


0.1214 


29.5 


0.8777 


7.309 


0.1368 


12.0 


0.9859 


8.211 


0.1218 


















30.0 


0.87S0 


7.286 


0.1373 


12.5 


0.9625 


8.182 


0.1222 


30.5 


0.8723 


7.264 


0.1377 


13.0 


0.9790 


8.153 


0.1227 


31.0 


0.8696 


7.241 


0.1381 


13.5 


0.9756 


8.125 


0.1231 


31.5 


0.8669 


7.218 


0.1385 


14.0 


0.9722 


8.096 


0.1235 


32.0 


0.8642 


7.196 


0.1390 


14.5 


0.9668 


8.069 


0.1239 


















32.5 


0.8615 


7.173 


0.1394 


15.0 


0.9655 


8.041 


0.1244 


33.0 


0.8589 


7.152 


0.1398 


15.5 


0.9622 


8.013 


0.1248 


33.5 


0.8563 


7.130 


0.1403 


16.0 


0.9509 


7.986 


0.1252 


34.0 


0.8537 


7.108 


0.1407 


16.5 


0.9556 


7.959 


0.1256 


34.5 


0.8511 


7.087 


0.1411 


17.0 


0.9524 


7.931 


0.1261 


















35.0 


0.8485 


7.065 


0.1415 


17.5 


0.9492 


7.904 


0.1265 


35.5 


0.8459 


7.044 


0.1420 


18.0 


0.9459 


7.877 


0.1270 


36.0 


0.8434 


7.022 


0.1424 


10.5 


0.9428 


7.851 


0.1274 


36.5 


0.8408 


7.001 


0.1428 


19.0 


0.9(96 


7.825 


0.1278 


37.0 


0.8383 


6.980 


0.1433 


19.5 


0.9365 


7.799 


0.1282 


















37.5 


0.8358 


6.960 


0.1437 


2D.0 


0.9333 


7.772 


0.1287 


38.0 


0.8333 


6.939 


0.1441 


20.5 


0.9302 


7.747 


0.1291 


38.5 


' 0.8309 


6.918 


0.1446 


21.0 


0.9272 


7.721 


0.1295 


39.0 


0.8284 


6.896 


0.1450 


21.5 


0.9241 


7.696 


0.1299 


39.5 


0.8260 


6.877 


0.1454 


22.0 


0.9211 


7.670 


0.1304 


















40.0 


0.8235 


6.857 


0.1459 


22.5 


0.9180 


7.645 


0.1308 


40.5 


0.8211 


6.837 


0.1463 


23.0 


0.9150 


7.620 


0.1313 


41.0 


0.8187 


6.817 


0.1467 


23.5 


0.9121 


7.595 


0.1317 


41.5 


0.8163 


6.797 


0.1471 


24.0 


0.9091 


7.570 


0.1321 


42.0 


0.8140 


6.777 


0.1476 


24.5 


0.9061 


7.546 


0.1325 


















42.5 


0.8116 


6.758 


0.1400 


25.0 


0.9032 


7.522 


0.1330 


43.0 


0.8092 


6.738 


0.1484 


25.5 


0.9003 


7.497 


0.1334 


43.5 


0.8069 


6.718 


0.1489 


26.0 


0.8974 


7.473 


0.1338 


44.0 


0.8046 


6.699 


0.1493 


26.5 


0.8946 


7.449 


0.1342 


44.5 


0.8023 


6.680 


0.1497 


27.0 


0.8917 


7.425 


0.1347 










1 








50.0 


0.7778 


6.476 


0.1544 


27.5 1 


0.8889 


7.402 


0.1351 


50.5 


0.7756 


6.458 


0.1548 



264 



OH FUEL 



Tablo €. Ten^enkturf Corrections to Apparent Decrees Baum^ of 

. Petrolioum Oils 

ThiB table givea the correctionfl to be subtracted from the apparent degrees Baum^of 
heavy petroleum oils (fuel. oils, lubrieating oils, etc.) at temperatures from 00 deg. to 
210 deg. F. to give the true degrees Baum^ at 60 deg. F. (modulus, 140). It is assumed 
that the hydrometer is of glass having a coefficient of cubical expansion of 0.000023 per 
deg. C.p and \b correct at 60 deg. F. 

(For more complete oil tables see Circular 57, Bureau of Standards) 



Observed degrees Baum6 

Obeerved 
tempera- 
tiwe, deg. 

^' 'Subtract from observed degrees Baum6 to obtain true degrees Bauni6 at 



14 



16 



18 



20 



22 



24 



26 



28 



30 



32 



34 



36 



60 
62 
64 
66 
68 

70 
72 
74 
76 
78 

80 
82 
84 
86 
88 

90 
92 
94 
96 
98 

100 
10$ 

no 

115 
120 

125 
130 
135 
140 
145 

150 
155 
160 
165 
170 

175 
180 
185 
190 
195 

200 
205 
210 



00 deg. F. 



0.0 
.1 
.2 
.3 
.4 

.5 
.6 
.7 

.8 1 
.9 

1.0 



0.0 
.1 
.2 
.3 
.4 

.5 
.6 
.7 
.8 
.9 

1.0 
I.I 
1.3 
1.4 
1.5 

1.6 
1.7 
1.8 
1.9 
2.0 

2.1 
2.4 
2.6 
2.9 
3.1 



0.0 
.1 ; 



.4 

.5 
.6 
.7 
.8 
.9 

1.1 
1.2 
1.3 
1.4 
1.5 

1.6 
1.7 
1.8 
1.9 
2.0 

2.2 
2.4 
2.7 
2.9 
3.2 

3.4 
3.7 
3.9 
4.2 
4.4 

4.7 
4.9 



0.0 
.1 
.2 
.3 
.5 

.6 
.7 
.8 
.9 
1.0 

I.I 
1.2 
1.3 
1.4 
1.6 

1.7 

1.8 
1.9 
2.0 
2.1 

2.2 
2.5 
2.8 
3.0 
3.3 

3.5 

3.8 
4.1 
4.3 
4.6 

4.8 
5.1 
5.3 
5.6 
5.8 

6.0 
6.3 
6.5 
6.8 
7.0 



I 



0.0 
.1 
.2 
.3 
.5 

.6 
.7 
.8 
.9 
1.1 

1.2 
1.3 
1.4 
1.5 
1.6 

1.7 
1.8 
1.9 
2.0 
2.2 

2.3 
2.6 
2.8 
3.1 
3.4 

3.6 
3.9 
4.2 
4.4 
4.7 

5.0 
5.2 
5.5 
5.7 
6.0 

6.2 
6.5 
6.7 
7.0 
7.2 

7.5 
7.7 
8.0 



0.0 


0.0 


.1 


.1 


.2 


.3 


.3 


.4 


.5 


.5 


.6 


.6 


.7 


.7 


.8 


.9 


.9 


1.0 


1.1 


1.2 



1.2 
1.3 
1.4 
1.5 
1.7 

1.8 
1.9 
2.0 
2.1 
2.2 

2.3 
2.6 
2.9 
3.2 
3.5 



.2 
.3 
.5 
.6 
.7 



1.8 
1.9 
2.0 
2.2 
2.3 

2.4 
2.7 
3.0 
3.3 
3.6 



3.7 


3.8 


4.0 


4.1 


4.3 


4.4 


4.6 




4.8 




5.1 




5.4 




5.6 




6.1 




6.2 




6.4 




6.6 




6.9 




7.2 




7.4 




7.7 


7.9 


7.9 


8.2 


8.2 


8.4 



0.0 

.1 

.3 
.4 
.5 

.6 

.7 

.9 

1.0 

1.2 

1.3 
1.4 
1.5 
1.6 
1.8 

1.9 
2.0 
2.1 
2.3 
2.4 

2.5 
2.8 
3.1 
3.4 
3.7 

4.0 
4.3 
4.6 
4.8 
5.1 

5.4 
5.7 
6.0 
6.3 
6.5 

6.8 
7.1 
7.3 
7.6 
7.9 

8.1 
8.4 
8.7 



0.0 


0.0 


.1 


.1 


.3 


.3 


.4 


.4 


.6 


.6 


.7 


.7 


.8 


.8 


.9 


.9 


1.1 


1.1 


1.2 


1.2 


1.3 


1.3 


1.4 


1.5 


1.5 


1.6 


1.7 


1.8 


1.8 


1.9 , 



2.0 
2.1 
2.2 
2.3 
2.4 

2.6 
2.9 
3.2 
3.5 
3.8 

4.1 
4.4 
4.7 
5.0 
5.3 

5.6 
5.9 
6.2 
6.5 
6.7 

7.0 
7.3 
7.6 
7.8 
8.1 

8.4 
8.7 
8.9 



2.0 
2.1 
2.2 
2.4 
2.5 

2.7 
3.0 
3.3 
3.6 
3.9 

4.2 
4.5 
4.8 
5.1 
5.4 

5.7 
6.0 
6.3 
6.6 
6.9 

7.2 
7.5 
7.8 
8.1 
8.4 

8.6 
8.9 
9.2 



2.1 
2.2 
2.3 
2.5 
2.6 

2.7 
3.1 
3.4 
3.8 
4.0 

4.3 
4.7 
5.0 
5.3 
5.6 

5.9 
6.2 
6.5 
6.8 
7.1 

7.4 
7.7 
8.0 
8.3 
8.6 

8.9 
9.2 
9.5 



0.0 
.1 
.3 
.4 
.6 

.8 

.9 

1.0 

1.2 

1.3 

1.4 
1.5 
1.7 
1.8 
2.0 



I 



0.0 
.1 
.3 
.4 
.6 

.8 

.9 

1.1 

1.2 

1.4 

1.5 
1.6 
1.8 
1.9 
2.0 

2.1 
2.3 
2.4 
2.5 
2.7 

2.8 
3.2 
3.5 
3.9 
4.2 

4.5 
4.8 
5.2 
5.5 
5.8 

6.1 
6.4 
6.7 
7.0 
7.3 

7.6 
8.0 
8.3 
8.6 
8.9 

9.2 
9.5 
9.8 



SPECIFIC GRAVITY 



265 



Tftble 7. Temperaturt Correetions to ApiMroit 8p. Or. of Petroleum 

Oils 

This table sirw the oorreetion to be added to apparent epecifio gravities of beavy 
petroleum oUs (fuel oile, lubrioating oils, etc.,) at temperatures of 60 deg. to 210 deg. F. 
to pve tbe true speoifio gravity of the oil at 60**/60** F. It is assumed that the hydrom- 
eter or pienometer used is of glass having a ooeiBoient of cubical expansion of 0.000023 
per deg. C. and is correct at 60 deg. F. (For more complete oil tables, see Circular 
67, Bureau of Standards). 











( 


Observed specific gravity 




Observed 


















tempera- 
ture, deg. 


0.850' 


0.860 


0.870 


0.860 


0.890 


0.900 0.910 


0.920| 0.930 


0.940 0.950| 0.960 


F. 


Add to observed specific gravity to give true specific gravity at 60V60* F. 


60 


O.OOO 


0.000 


O.OOO 


0.000 


0.000 


0.000 


0.000 


0.000 


0.000 


0.000 


0.000 


0.000 


62 


O.OOI 


O.OOI 


0.001 


O.OOI 


O.OOI O.OOI 


O.OOI 


O.OOI 


O.OOI 


O.OOI 


O.OOI 


0.001 


64 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


66 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


0.002 


68 


0.003 


0.003 


0.003 


0.003 


0.0031 0.003 


0.003 


0.003 


0.003 


0.003 


0.003 


0.003 


70 


0.004 


6.004 


O.0O4 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.0D4 


72 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


0.004 


74 


0.005 


0.005 


0.005 


0.005 


0.005 


0.005 


0.005 


0.005 


0.005 


0.005 


0.005 


0.005 


76 


0.006 


0.006 


O.OOS 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


78 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


0.006 


80 


0.007 


O.Q07 


0.007 


0.007 


0.007 


0.007 


0.607 


0.067 


0.007 


0.007 


0.007 


0.007 


82 


0.008 


0.006 


0.006 


0,006 


0.006 


0.007 


0.007 


0.007 


0.007 


0.007 0.007 


0.007 


84 • 


0.009 


0.006 


0.008 


0.006 


0.066 


' 0.006 


0.006 


0.008 


0.006 


0.006 0.008 


0.006 


86 


0.009 


0.009 
0.010 


0.009 


0.009 


0.009 


, 0.009 


0.009 


0.009 


0.009 


0.009 0.009 


0.009 


88 


0.010 


o.oto 


O.OIO 


O.oto 


O.OIO 


0.010 


0.010 


O.OIO 


O.OIO 


O.OIO 


0.010 


90 


0.011 


0.01 1 


0.01 1 


o.on 

O.ON 


O.OIO 


O.OIO 


O.OIO 


O.OIO 


0.010 


O.OIO 


0.010 


O.OIO 


92 


0.011 


0.01 1 


O.OII 


0.011 


I O.OII 


O.OII 


O.OII 


O.OII 


O.OIti 


0.011 


O.OII 


94 


0.012 


, 0.012 


0.012 


0.012 


0.012 


0.012 


0.012 


0.012 


0.012 


0.012 


0.012 


0.012 


96 


0.013 


o.on 


0.013 


0.013 


0.0131 0.013 


0.012 


0.012 


0.012 


0.012 


0.012 


0.012 


96 


0.014 


0.013 


9.613 


0.013 


0.013 


• 0.013 


0.013 


0.013 


0.013 


0.013 


0.013 


0.013 


100 


0.014 


0.014 


0.014 


0.014 


0.014 


0.014 


0.014 


0.014 


0.014 


0.014 


0.014 


0.014 


105 


0.016 


0.016 


0.016 


0.016 


0.016 


0.016 


0.016 


0.016 


0.016 


0.016 


0.016 


0.016 


110 


0.018 


0.018 


0.018 


0.018 


0.017 


0.017 


0.017 


0.017 


0.017 


0.017 


0.017 


0.017 


115 


0.020 


0.020 


0.020 


0.020 


0.019 


0.019 


0.019 


0.019 


0.019 


0.019 


0.019 


0.019 


120 


0.022 


0.021 


0.021 


0.021 


0.021 


0.021 


0.021 


0.021 


0.021 


0.021 


0.021 


0.021 


125 


0.023 


0.023 


0.023 


0.023 


0.023 


0.023 


0.023 


0.023 


0.023 


0.022 


0.022 




130 


0.025 


0.025 


0.025 


0.025 


0.025 


0.024 


0.024 


0.024 


0.024 


0.024 


0.024 




135 


0.027 


0.027 


0.026 


0.626 


0.026 


0.026 


0.026 


0.026 


0.026 


0.026 


0.026 




140 


0.028 


0.028 


0.028 


0.028 


0.026 


0.028 


0.028 


0.028 


0.028 


0.027 


0.027 




145 


0.030 


0.030 


0.030 


0.030 


0.030 


0.030 


0.029 


0.029 


0.029 


0.029 


0.029 




ISO 


0.032 


0.032 


0.032 


0.0)1 


0.031 


0.031 


0.031 


0.0)1 


0.031 


0.031 


0.031 




155 


o.m 


0.033 


0.033 


0.033 


0.033 


0.033 


0.033 


0.033 


0.033 


0.033 






160 


0.035 


035 


0.035 


0.035 


0.035 


0.035 


0.034 


0.034 


0.034 


0.034 






165 


0.037 


0.037 


6.037 


0.037 


0.036 


0.036 


0.036 


0.036 


0.036 


0.036 






170 


0.039 


0.039 


0.038 


0.038 


0.038 


0.038 


0.038 


0.038 


0.038 


0.037 






175 


0.040 


0.040 


0.040 


0.040 


0.040 


0.040 


0.039 


0.039 


0.039 


0.039 






180 


0.042 


0.042 


0.042 


0.041 


0.041 


0.041 


0.041 


0.041 


0.041 


0.041 






185 


0.044 


0.044 


0.043 


0.043 


0.043 


0.043 


0.043 


0.043 


0.042 








190 


0.045 


0.045 


0.045 


0.045 


0.045 


0.044 


0.044 


0.044 


0.044 








195 


0.047 


0.047 


0.047 


0.047 


0.046 


0.046 


0.046 


0.046 


0.046 








200 


0.049 


0.049 


0«048 


0.046 


0.048 


0.048 


0.048 


0.048 0.047* 








205 


0.051 


Q.QSO 


0050 


0.050 


0.05Q 


0.050 


0.049 


0.0491 0.049' 








210 


0.052 


0.052 


0.052 


0.051 


0.051 


0.051 


0.051 


0.05r 0.051 









266 



OIL FUEL 



Table 8. Ixpantioii Table for Oil Fuel 

Thia table, from Bureau of Standard« Circular No. 57 shows volume that would be 
oooupied at 00 deg. F. by a quantity of cnl, of various specifio gravities, occupying unit 
volume at the designated temperatures. Example: 1 gal. oil measured at 98 deg. F. 
having sp. gr. 0.86 at this temperature, will occupy volume of 0.088 gal. at 60 deg. F. 
"Observed temperature," and ''observed sp. gr." refer to true indications of instruments 
corrected for instrumental errois. 











Observed apecifi< 


D gravity 






Observed 
temperature 
in deg. F. 


0.800 

1 


0.810 


0.820 


0.630 


0.840 


0.850 


0.860 


0.870 


1 0.868 


Volume at 60 deg. F. occupied by unit volume at various temperatures 


30 

32 


1.016 
1.014 
1.013 
1.012 
1.011 

1.0105 
1.0095 
1.0065 
1.0075 
1.0060 

1.0050 
1.0040 
1.0030 
1.0020 
I.OOIO 

1.0000 
.9990 
.9960 
.9970 
.9960 

.9950 
.9940 
.9930 
.9920 
.9910 

.990 
.989 
.968 
.967 
.966 

.965 
.964 
.983 
.962 
.961 

.980 
.979 
.979 
.978 
.977 

.976 
.975 
.974 
.973 
.972 

.971 


1.015 
1.014 
1.013 
1.012 
1.011 

l.OIOO 
1.0090 
1.0060 
1.0070 
1.0060 

1.0050 
1.0040 
1.0030 
1.0020 
1.0010 

1.0000 
.9990 
.9960 
.9970 
.9960 

.9950 
.9945 
.9935 
.9925 
.9915 

.990 
.969 
.968 
.967 
.967 

.966 
.965 
.964 
.963 
.982 

.961 
.980 
.979 
.978 
.977 

.976 
.976 
.975 
.974 
.973 

.972 


1.015 
1..014 
1.013 
1.011 
1.010 

1.0095 
1.9090 
1.0080 
1.0070 
1.0060 

i:oo50 

1.0040 
1.0030 
1.0020 
1.0010 

1.0000 
.9990 
.9960 
.9970 
.9960 

.9950 
.9945 
.9935 
.9925 
.9915 

.990 
.969 
.969 
.968 
.967 

.966 
.965 
.964 
.983 
.962 

.961 
.980 
.960 
.979 
.978 

.977 
.976 
.975 
.974 
.973 

.973 


1.014 
1.013 
1.012 
1.011 
1.010 

1.0095 
1.0065 
1.0075 
1.0065 
1.0060 

1.0050 
1.0040 
1.0030 
1.0020 
1.0010 

1.0000 
.9990 
.9965 
.9975 
.9965 

.9955 
.9945 
.9935 
.9925 
.9915 

.991 
.990 
.969 
.968 
.967 

.966 
.985 
.965 
.984 
.963 

.962 
.961 
.980 
.979 
.978 

.977 
.977 
.976 
.975 
.974 

.973 


1.014 
1.013 
1.012 
1.011 
1.010 

1.0095 
1.0085 
1.0075 
1.0065 
1.0055 

1.0045 
1.0035 
1.0025 
1.0020 
1.0010 

1.0000 
.9990 
.9965 
.9975 
.9965 

.9955 
.9945 
.9940 
.9930 
.9920 

.991 
.990 
.969 
.968 
.967 

.967 
.986 
.965 

.964 

.963 

.962 
.961 
.961 
.960 
.979 

.978 
.977 
.976 
.975 
.974 

.974 


1.014 
1.013 
1.012 
1.011 
1.010 

1.0090 
1.0060 
1.0075 
1.0065 
1.0055 

1.0045 
1.0035 
1.0025 
1.0020 
1.0010 

I.OOQO 
.9990 
.9965 
.9975 
.9965 

.9955 
.9945 
.9940 
.9930 
.9920 

.991 
.990 
.989 
.968 
.967 

.967 
.966 
.965 
.964 
.963 

.962 
.962 
.961 
.960 
.979 

.978 
.978 
.977 
.976 
.975 

.974 


1.013 
1.012 
1.011 
1.010 
1.009 

1.0090 
1.0080 
1.0070 
1.0065 
1.0055 

1.0045 
1.0035 
1.0025 
1.0015 
1.0010 

1.0000 
.9990 
.9965 
.9975 
.9965 

.9955 
.9945 
.9940 
.9930 
.9920 

.991 
.990 
.969 
.969 
.988 

.987 
.966 
.965 

. to4 

.964 

.963 
.962 
.961 
.960 
.960 

.979 
.978 
.977 
.976 
.975 

.975 


1.013 
1.012 
1.011 
1.010 
 1.009 

1.0090 
1.0080 
1.0070 
1.0060 
l.OQSO 

1.0045 
1.0035 
1.0025 
1.0015 
1.0010 

1.0000 
.9990 
.9985 
.9975 
.9965 

.9960 
.9950 
.9M0 
.9935 
.9925 

.991 
.991 
.990 
.989 

• TOO 

.967 
.986 
.965 
.965 
.964 

.963 
.962 
.961 
.961 
.980 

.979 
.978 
.977 
.977 
.976 

.975 


1.013 
1.012 


34 


I.Oll 


36 


I.OIO 


38 


1.009 


40 

42 


1.0085 
1.0075 


44 


1.0070 


46 


1.0060 


48 


I.OOSO 


50 

52 


1.0045 
1.0035 


54 


1.0025 


56 


1.0015 


58 


1.0010 


60 


1.0000 


62 


.9990 


64 

66 


.9985 
.9975 


68 


.9965 


70 

72 


.9960 
.9950 


74 

76 

78 

80 


.9940 
.9935 
.9925 

.992 


82 

84 

86 


.991 
.990 
.969 


88 




90 


.967 


92 

94 

96 


.967 
.966 
.985 


98 

100 

102 

104 


.964 

.963 
.963 
.962 


lOS 

108 


.981 
.960 


110 

112 


.979 
.979 


114 

116 


.978 
.977 


118 


.976 


120 


.976 



EXPANSION 



267 



T»bl« 8. KspMUion Table for OH Fatl. — Continued 







( 


Observed apecifio 


gravity 






ObMrved 
temperature 


0.090 1 


0.900 1 

1 

le at 60' 


0.910 


0.920 


0.930 


0.940 1 

1 


0.950 




Volun 


F. occupied by unit volume at various 
temperatures 


30 


1.013 
1.012 
1.011 
1.010 
1.009 

1.0085 
1.0075 
1.0070 
I.006O 
1.0050 

1.0040 
1.0095 
1.0025 
1.0015 
1.0010 

1.0000 
.9990 
.9985 
.9975 
.9970 

.9960 
.9950 
.9945 
.9935 
.9925 

.992 
.991 
.990 
.989 
.988 

.988 
.967 
.966 
.985 
.985 

.^84 
.983 
.982 
.981 
.981 

.980 
.979 
.978 
.977 
.976 

.976 


1.012 
1.011 
1.010 
1.010 
1.009 

1.0080 
1.0075 
1.0065 
1.0060 
l.OOSO 

1.0040 
1.0035 
1.0025 
1.0015 
1.0010 

1.0000 
.9995 
.9985 
.9980 
.9970 

.9960 
.9955 
.9945 
.9935 
.9930 

.992 
.991 
.990 
.989 
.988 

.968 
.987 
.986 
.965 
.965 

.964 
.963 
.982 
.981 
.981 

.980 
.979 
.978 
.978 
.977 

.976 


1.012 
1.011 
1.010 
1.009 
1.009 

1.0080 
1.0075 
1.0065 
1.0060 
1.0050 

1.0040 
1.0035 
1.0025 
1.0015 
1.0010 

1.0000 
.9995 
.9985 
.9960 
.9970 

.9960 
.9955 
.9945 
.9935 
.9930 

.992 
.991 
.990 
.990 
.969 

.988 
.967 
.986 
.985 
.985 

.984 
.983 
.982 
.982 
.981 

.960 
.979 
.978 
.978 
.977 

.976 


1.012 
1.011 
1.010 
1.009 
•1.008 

1.0080 
1.0070 
1.0065 
1.0055 
l.OOSO 

1.0040 
1.0030 
1.0025 
1.0015 
1.0010 

1.0000 
.9995 
.9965 
.9980 
.9970 

.9960 
.9955 
.9945 
.9935 
.9930 

.992 
.991 
.990 
.990 
.989 

.968 
.987 
.986 
.986 
.985 

.964 
.983 
.983 
.962 
.981 

.960 
.980 
.979 
.978 
.977 

.976 


1.012 
1.011 
1.010 
1.009 
1.006 

1.0080 
1.0070 
1.0065 
1.0055 
l.OOSO 

1.0040 
1.003O 
1.0025 
1.0015 
1.0010 

1.0000 
.9995 
.9985 
.9980 
.9970 

.9960 
.9955 
.9945 
.9935 
.9930 

.992 
.991 
.990 
.990 

.988 
.987 
.967 
.966 
.985 

.984 
.984 
.983 
.982 
.981 

.981 
.980 
.979 
.978 
.978 

.977 


1.012 
1.011 
1.010 
1.009 
1.008 

1.0080 
1.0070 
1.0060 
1.0055 
1.0045 

1.0040 
1.0030 
1.0025 
1.0015 
1.0010 

1.0000 
.9995 
.9965 
.9960 
.9970 

.9960 
.9955 

.9940 
.9930 

.992 
.991 
.990 
.990 
.989 

968 
.967 
.987 
.986 
.985 

.984 
.984 
.963 
.982 
.962 

.961 
.980 
.979 
.979 
.978 

.977 


1.011 


32 

34 


l.OtI 
1.010 


36 


1.009 


38 


1.008 


40 


1.0080 


42 


1.0070 


44 


1.0060 


46 


1.0055 


48 


1.0045 


SO 


1.0040 


52 


1.0030 


54 


1.0025 


56 


1.0015 


58 


1.0005 


60 


1.0000 


62 


.9995 


64 


.9965 


66 


.9960 


66 


.9970 




.9965 


72 


.9955 




.9945 


76 

78 

80 


.9940 
.9930 

.992 


82 


.991 


84 


.991 


86 


.990 


88 


.969 




.968 


92 


.968 


94 

96 


.987 
.966 
.985 


100 

102 

104 


.985 
.984 
.963 


106 •. 


.983 


108 


.982 


110 

112 


.981 
.961 




.960 


116 

lis 

V» 


.979 
.978 

.978 







Spodfle Heat of Oil varies with its composition. It increases with an 
increase of hydrogen content and decreases with increase of carbon content. 
The following figures* table 9, are reproduced from Holde*9 work on Examina- 
tion of Hydroearbon (Hit. 



OIL Pl'KL 

Bpwifla OraTlty uid SpeolAo HMt of CrudM 




Fia. 8. — Peniky-Martens closed-cup tester, (a) oH cup; <b) tit jkcket; 
(c) stirrer abaft; (d) stiirer; (r) brass mantle; (/) eraduatjoa niHrk; (0) flKme 
sdjiisMr; (ft) safety ligbt; (i) tbermometer; 01 pilot lilbt. 

tbna Pennsarlvania oil. Thia differenca, however, would be corrected largvly 
by difference in specific gravity. 

Ths Flklh Point of an oil is the temperature at which the oil, upon 
beiog heated slowly, gives off sufficient vapor to form over its surface. 



FLASH AND FIRE POIMTS 26B 

with tbe air present, an eiplodve mixture. It ii determined )q> heatine th» 
oil bud. as the temperature risea. tvatins it with a spark or flame until the 
luh ucjcurs. Oil may be stirred (aa in the Pe7iski/-M arlen tester) in order 
to ^t a unifomL temperature and thia temperature muat be accurately 
msuured. Conditions of the teat may iutroduce wide diSerencea in reaulta. 
TbuB, merely by oloaiOB is the top o[ the teet vcoael, the flash will be 
deUcMd sooner and at a lower temperature than if the Tessel is open, a* in 




Fio. 9. — Ta^Iabne open 



Pia. 10. — Cleveland open tester. 



the Tagliabue method. The former ia the cltravd cup nwtbod and the 
litter is the open oup. The closed cup is the more accurate method 
sod instnimentiB devised by Penikv-Marien and by Abel are recogniied as 
standards for fuel oil. 

Tbs nre Point, or burning point, is the temperature at which sufficient 
vapor is given off to remain ignited after Sashing. As a free aupply oJ oxygen 
is required, this test is made with the open oup. 

TssUng Ux Flaalk folnt. In the Fsnaky-ltanaii Apparacos. Fig. 8. a is the oil 
container wbioh can Ik clo«d by  tlfhtly Bltini lid. II is placed in a hMlini air 



ori£c« in the caytt, sod umuIUncoiuly > )M of flame J Iruru the tHt jet, li |j11«l go 
the lurfboe of the uEt- 

Opamtion. All nUr miBt be removed from the oil before teatinc by Gltcriag 
thTouih one of the biuU lelt filten of Che outfit. When the 
•unple ii icKly. tho oU cup it filled to toatk f, oo-nt u cloKd 
■nd the oil u npidly heited ualil its temperaluie is about SO 
del- F. below the expected fluh point. Wire (buis wreen, Fig. 

retvded to about S iet' per luio. Handle d it turned eon- 
tinuouiiy mod slowly. At intervals of 5 deg, ri*e in temperature, 
reduood to 3 deg. wbsn Dsnr Ibe eipgcl«d fluh poiac, n is turned, 
tbul opening the abutter and tilting flame into cup. The flaah 

■ample esn be uwd for but one teal, aiane at the first lest some 
of the more volatile product* are driven off thus raising the 
flash p<Hat of the rommijung oil. 

TMtiiic (or nra Point. The Tagliabue, Hg. S, and Cleve- I 
land, Fig, 10, Open Testers are beat adapted for this wcrk. 

Wftter and 8edlm«iit. Though water ia slightly 
■olublo in oils, for practical purposes the enginder is 
only interested in thew&ter present in m*«hajilcAl 

tugpatulon. Water and sediment are generally reported p^^ ^ | j^ and 

combined in percentage by vtdume but it is much better centrifuge 

to record them teparately. 

To determine ttie percentage of water and sediment in any oil, mil 50 
C.c. of the oil under test with SO c.e. of benzol in a MPtrlfugg gTMltWta, 
Figs. II and 12. Then centrifuRe until a clear line o( demarkatiun is visible 
between the oil, water and sediment.- 



Fio. 12.— Electric centrifuge. 
The oil may be thinned with lawUne, but this is objectiona 

but its use will ^ve a Iri^ indicatjoo of tbo prvaorioe of water. 

Carbon dlaulphide is recommeuded bj some aatharitiee as pi 
[m tbinalBg (he oil, a* Um latter will not dissolve the free carbon ic 
portion a( wliish la tberelai* depoaited as sediment. 



WATER AND SEDIMENT 271 

The most aoeurate method of determining peroentace of water and eediment is by 
meana of distillation in the preeenoe of an esoees of hydrocarbons, but this is fwonfiBllj 
a laboratory method. 

If no ceotrifuse is available a 50 c.c. sample of oil thinned with 50 c.c. of 
benz(^ may be allowed to stand for several hours in a slender graduate. 
Water and sediment will settle to the bottom to some extent^ but a true read- 
ing is not obtained in this way. This method will only indicate when large 
quantities of water or sediment are present. The following tests, 50 c.c. 
of oil known to contain 2.0 per cent of water and sediment being used for 
test, were conducted at the Navy Fuel Oil Testing Plant to show the relative 
efficiency of settling test with and without oentrifuging: 



Stood for 16 

hoiuB, per 

cent of water 

and sediment 



Heated and allowed 

to stand 6 hours, 

per cent of water 

and sediment 



With bensol | 6.1 0.2 

With gasoline , 0.0 0.0 

With kerosene ?-P__ '. JP 

With bensol and centrifuged 2.0 

Tbo Centrilugs, as employed for centrifugal separation of water and 
sediment from oil, can be obtained as a hand or power operated machine. 
In either case it consists of a vertical spindle, capable of rotation, which 
carries a head for test tubes. Oil to be tested is placed in the tubes. As 
the head is revolved, the test tubes which are held in gimbal-like collars 
assume horisontal positions and the water and sediment are thrown to 
the bottom of the tube by the centrifugal action. 

The BinMT and Amtnd hand operated instrument, Fig. 11, has a gear 
ratio between handles and revolving head of 15 to 1. It can be operated 
at 1500 R.P.M. with two 15 c.c. graduated tubes charged. This type is 
supplied to ships. The laboratory instrument. Fig. 12, is an electrically 
driven machine made by the InlerruUional Inairumeni Co, It has a maximum 
speed of 3000 R.P.M. and can be supplied with a variety of heads as 
illustrated. Tubes of 15 c.c. and 50 c.c. can be used with this machine. 

Bpeciflcationf. The following are specifications as adopted by the Com- 
mittee on Standardization of Petroleum Specifications, XT. S. Fuel Admin- 
istration, October 2, 1918: 

Metliods of Test, (a) Flash point will be taken as indicated in the specifioationB. 

(6) Viscosity will be taken by the Engler Viscoeimeter. (See note under "Specifica- 
tions.") 

(c) Water and sediment will be taken by the distillatioa method. When oil in 

•man lots is consigned to naval vessels or to navy yards the oentrif uge .test will be used 

( n order to obviate delay. In this test 30 c.o. of oil and an equal quantity of best 

eommenaal bensol, 60 per cent white, will be used, and the mixture heated to 100 deg. F. 

Navy Standard Fuel Oil. (a) Fuel oil shall be a hydrocarbon oil free from grit, add. 
and fibrous or other foreign matter likely to clog or injure the burners or valves. If 
required by the Navy Department, it shall be strained by being drawn through filters 
of wire gause having 16 meshes to the inch. The clearance through the strainer shall 
be at least twice the area of the suction pipe and strainers shall be in duplicate. 

(6) The unit of quantity to be the bbl. of 42 gal. of 231 ou. in. at a standard tem- 
perature of 60 des. F. For every decrease or increase of temperature of 10 deg. F. (or 
proportion thereof) from the standard, 0.4 of 1 per cent (or prorated percentage) shall be 
added or deducted from the measured or gauged quantity for correction. 



272 OIL FUEL 

(c) The fluh point ehall not be lower than 150 deg F. as a minimum (Abel or Pensky- 
Marten's oloeed cup) or 175 deg. F. (Tagliabue open oup). In case of oils having a vis- 
cosity greater than 8 Engler at 150 deg. F. the flash point (closed cup) shall not be below 
the temperature at which the oil has a viscosity of 8 Engler. 

{d) Viscosity shall not be greater than 40 Engler at 70 deg. F. 

(e) Water and sediment not over 1 per cent. If in excess of 1 per cent, the excess 
to be subtracted from the volume; or the oil may be rejected. 

(/) Sulphur not over 1.6 per cent. 

Note. If the Engler viscosimeter is not available, the Saybolt Standard Universal 
viscoaimeter may be used. Equivalent viscosities: 
8 Engler » 900 seconds Saybolt. 
40 Engler- 1500 seconds Saybolt. 

Sp«eUl Spaelfleatioiis for Oat Oil for DIomI Xncinos. 1. Flash point not lower 
than 150 deg. F. (Abel or Pensky-Marten's closed cup). 

2. Water and sediment, trace only. 

3. Asphaltum, none. 

Bunkar Oil "A." To comply strictly with the provisions for Navy specifications 
fuel oil, except that there shall be no limit on sulphur. 

Bunker Oil "B.'' Specifications to be the same as for Navy Standard fuel oil except : 
(c) Omit and substitute "The Flash point shall not be lower than 150 deg. F. as 
a minimum Abel or Pensky-Marten's closed cup) or 175 deg. F. (Tagliabue open cup) . 
id) Omit and substitute "To have a minimum gravity of 18 Baum6. 
CO Omit. 

Bunker Oil "C." Specifications to be the same as for bunker oil '*B" except it is 
to have a gravity of approximately 16 Baum6. 

UsM of Various Orades. Navy standard fuel oil only will be supplied 
to battleships, destroyers aad other vessels subject to heavy forced draft 
conditions or require^ to run smokeless. It will also be supplied for cargo 
oil for all shipments abroad or to Navy storage. 

Bunker Oil "A" will be used by other types of veaaels requiring a light oil 
and by shore stations fitted with separate storage for yard use. It will not 
not be used where bunker oil '*B" or "C" can be satisfactorily used. 

Bunker Oil "B" will he used by all transports and cargo vessels which 
can satisfactorily burn an oil not heavier than 18 Baum4 gra\ity. It will 
not be used where bunker oil "C" can be satisfactorily used. 

Bunker Oil "C" will be used by all transports and cargo vessels which can 
satisfactorily burn an oil of approximately 15 6aum6 gravity. 

Oil Measurement. For contract purposes and bunker and tank meas- 
urement the standard unit is the U. S. gallon (231 cu. in.). The litre 
(1 gal. — '3.785 litres) and the imperial gallon (4.54 litres) are used abroad. 
U. 8. bbl. = 42 U. S. gallons. Imperial bbl. = 50 U. S. 

Voluxnetric measurement of oil should always be based on a standard temperature 
(in U. 8. A . , 60 deg. F.), See Coef. Exp., p. 262. The Navy department specifies 60 deg. 
F., and a correction of 0.4 of 1 per cent is made for each 10 deg. variation from thia 
standard. Tank Soundings and oil meters, page 318, are the practical measuring agenta 
used on shipboard. 

For the calculation of evaporative results, fuel used for power, heat value, 
etc., units of weights are employed, i.e., lb., kilo, etc. 

Corrosion Due to Oil. The much prophesied deleterious effects of 
sulphur in oil on boiler tubes has not developed in practice. In cases of 
neglect, pitting may occur, under certain conditions, but will not exceed in 
magnitude the same effects with coal of equal sulphur contents under the 
same conditions. However, high sulphur oils will attack copper and for 



CONSBRVATION 



273 



this reason fuel oil pipes and heating coils are made of steel. Brass and 
bronze fittings in pumps and pipes lines are quite safe. 

Compartments and tanks used for the storage of fuel oil should not be 
painted on the inside, but should be protected .from corrosion either by the 
oil itself or by some special coating. 

The inside of compartments and tanks used for carrying fuel oil shall be 
inspected every twelve months and the plating or bulkheads separating 
fueJ oil compartments from others shall be carefully examined for leaks 
during the quarterly inspection and also each time oil is taken on board. 

GoiUMiTatioii. Generally speaking, conservation is best promoted by 
using oil of the highest viscosity and the highest apparent stilphur content that 
will give the desired results. This is apparent from the specifications on 
page 271, which specifications were primarily drawn up in the interest of 
conservation. 



Air Plp« to AkiBMrher* 



riiiiBg pip« 



1-8 



Qalek 

CItMlDg 

Voire 



-tCiil 




z^ 



^1.8 riiiim Pipe 



^g VAIr yiptog from Oil TankB 



■M- 



EO*-- 



10 OT«rflow Yftlrt 



BeUy Tank 




■Oaage Glaii 



^ ^Filling Pipe to DUtribotiai Manifold 



.yvvv 



TfF. 



[ 



vvvy 



m 




FiQ. 13. — Filling pipes and relay tanks, U. S. S. Pennsylvania. 



Storage on Board Ship. Whereas eoal must be stored adjacent to 
fiierooms, fuel oil is adaptable to storage in almost any part of the vessel, in 
bunker spaces, tanks remote from firerooms, and double bottoms. While 
easily handled by pumps, the feasibility or its nse on shipboard depends 
primarily in the ability to keep it where stored until pumped to boilers. 
Fitting oil tight tanks to steamers increases the structural cost over coal 
bumeiB. 

The tanks must be fitted with swash plates, il deep, expansion trunks 
to allow for increase in volume due to heating, vent pipes carried above the 
main deck and fitted with goosenecks and gause screens to liberate oil vapors* 
find sounding pipes for measuring depth oi oil in the tanks. These should be 
of ample sise, not less than 2^^ in., and small holes should be drilled in these 
18 



274 OIL FUEL 

pipes to give free acoess to the oO at all depths, aa it is posBible for some 
difference in density to exist at various levels, if the oil has been standing for 
some time. To prevent undue pressure being put on closed tanks, due to 
too rapid filling, the combined area of the vents and sounding pipes must 
be sufficient to provide adequate overflow. For this reason, when tanks 
in the lower part of the vessel, such as the double bottoms, are used for oil, 
a system of ralay tanks, Fig. 13, is fitted to eliminate danger of a large head 
of oil exerting heavy pressure on the storage tanks. 

A filling pipe on each aide of the ship runs to the relay tank. The latter is fitted with 
a removable cover and a large overflow dosed by a relief valve with a very light tpring. 
Filling pipee lead from the relay tank to the storage tanks, and the greatest pressure that 
can be put on the latter is that due to the head from the relay tank, which can be reduced 
to a snutU amount by suitably locating such tank. The vent pipes from the storage 
tanks lead into the relay tank, which is fitted with a common vent pipe leading to the 
atmosphere and covered at the end with wire gauae. The supply pipes to the relay 
tanks are fitted with quick closing valves and the relay tank is equipped with a gage 
glass to mark the level of oil. Also an annunciator at the relay tank, operating from 
pneumeroators fitted in the storage tanks, gives warning when the latter are 05 per cent 
full. 

The use of fittings of any kind on the outside of tanks below the oil level 
is very bad practice. The storage tank has a high and low suction, i.e., 
two pipes either separate or connected through a manifold, one taking the 
oil from a level 12 or 18 inches from the bottom of the tank and the other from 
a point within a few inches of the bottom. The upper suction is used for 
regular service, and at all times except in emergency or when the supply 
is very low or when the low suction is employed to pump overboard water 
or very dirty oil which has accumulated at the bottom of the tank. 

8AF1TT PRSCAirriONB TOR OIL-BUBNINO VBSSBU 

Fuel oil is inert, non-explosive, very difficult to ignite in bulk, and not 
capable of spontaneous combustion. However, the Tapor from thii oil 
il ezploglTe when mixed with air. This vapor is heavier than air and tends 
to accumulate in low levels, such as bilges and bottoms of tanks; it is 
always present in a partly filled oil tank, or in one that has contained fuel 
oil and from which the vapor has not been removed by artificial means. It 
is expelled through the vents from fuel oil tanks while they are being filled. 
Ignition may be caused by an open light, electric spark, or spark made by- 
striking metal, heat of the filament of a broken electric lamp, smoking, 
sparks from smoke pipe or galley, or fire under boilers. An oil fire may be 
extinguished by dry sand, steam, or chemical extinguishers, but not by 
water. 

While oil il being received on board no naked light, smoking, or 
electrical apparatus liable to spark should be jsermitted within 50 feet of 
an oil hose, tank, compartment containing a tank, or the vent from a tank. 
Storage tanks should be closely watched for leaks. 

Precautions against Danger on Shipboard. Oil in bulk is perfectly 
safe so long as its flash point is more than 60 deg. F. above the temperature 
to which it is exposed. Not being subject to spontaneous combustion, oil 
bunker fires are practically unknown at sea. 

The V. S. Navy, in cooperation with the Biuvau of Mines, investigated the matter of 
possible explosion of gases in storage tanks, and it was found that no inflammable gases 
were formed in any amount in the storage tanks or bunkers until the oil was heated to 
the flash point. It was also found that any oil in the bunker tank had to be heated to 



SAFETY PRSCAUTIONS 275 

within 60 dec. F. of the flash point before eren » feint slow or peitiel burning wee ob- 
teined on introduoing e naked flame. 

No i>er8on should be allowed to eiiter a fuel oil tank until it has been 
freed of gas by the use of water or steam, and then Anyone entering such 
tank should have a life line aroimd his body, properiy tended, in order that 
he may be hauled out if overcome by gas. 

All bunkon must b« Tontilfttod by vents, the openings of which 
must be lead well away from possible exposure of flame. No smoking should 
be idlowed in the vicinity of the vent. Wire iriiUBe proteoton in these 
vents must be kept intact. Bunker bulkheads exposed to heat must be 
insulated. Bunkers should never be more than 95 per cent, full, to allow 
for expansion of the oil. Bunl.ers and fire rooms should be fitted with 
tank type steam or chemical unotherinf apparatus; see p. 327. 

No naked light, smoking, or electrical fuses, switches (unless enclosed type), 
or other apparatus liable to spark should be permitted in a compartment con- 
taining a fuel oil tank or fuel oil pumps or piping, except that smoking 
may be permitted in the engine rooms and on fireroom floor in front of boilers 
which are in operation. Electric lamps, see p. 1372, used in such compart- 
ments should have steam-tight globes, or be of a type that will insure break- 
ing the circuit through the lamp in case the bulb breaks. 

The TalT6t on f Um gaugM fitted to the storage or settling tanks should 
be kept habitually shut. Valves may be opened to read the gauge but they 
should be shut again immediately thereafter. 

Whenever the fuel oil tanki are to remain empty for any length of 
time, or whenever they are to be entered, or whenever any work is done in 
them requiring heated rivets, hammering, etc., or any lights other than 
portable electric (which lights should be tested before use), or whenever 
such work is done in the vicinity of open tanks or pipes, all such tanks 
and all pipes leading thereto should be cleared of vapor, after the fuel oil has 
been removed, by blowing through live steam, or air by means of portable 
Mower, for at least 12 hours. 

When vessels carrying fuel oil are in dry dock, no oil -. nould be allowed 
to drain into the dock. Should it be necessary to remove oil from tanks or 
receptacles on vessels in dry dock« such precautions should be taken as will 
prevent any of the oil reaching the floor of the dock or escaping so as to permit 
the accumulation of explosive vapors in the dock. 

8A7BTT FRSCAUnOHS FOE VBS8XL8 OA&BYINa OIL 

CA&OOX8 

VesBels carrying oil cargoes should observe all rules and safety precautions 
prescribed for ofl-buming vessels, see p. 274, and in addition the following 
special rules should be followed: 

While oil is on board no smoking, except in officers' rooms and crew's 
spaces, or naked lights should be allowed on board. Waste, oilskins, paints, 
or other oombuitible material should not be stored in pump rooms. 
Oily waste should be destroyed by burning under the boilers. The use 
of other than Safety matches should be prohibited. 

All access hatches and manholes to fuel oU tanks should be painted red 
and fitted with locks, and labU plates should be secured thereto, stating 
that the hatch affords access to an oil tank. 

Xloctrieal apparatus should be frequently insx>ected and any condition 
liable to lead to sparking remedied at once. Fuses, switches, etc., between 



276 OIL FUEL 

decks or in oth«r than officers' rooms and crew's spaces, should be protected 
by flame proof wire gause. 

Protable electric lights, if used, should be fitted with steam-tight globes and 
heavy wire guards or other suitable devices to prevent the ignition of vapor 
from the heat of the filament in the event of breaking the bulb. 

When loading or discharging cargo or when freeing the tanks of gas, doors to 
boiler rooms and living quarters and all air porta should be closed; galley fires should be 
exttnguisfaod, if practical, otherwise the doors and opeoinga to galley should remain 
olosed; there should be no fire in donkey boiler; tugs or other steam vesaela should not 
be allowed alongside when hatches are c^>en. When loading or discharging at night, 
no lights should be oarried around on deck. Water-tight clusters should be suspended 
in the rigging at a safe distance from deck, and the wires should not be dragged across 
the deck. During the period of loading no naked lights or Rmoking should be allowed 
on board ship or within 50 feet of the oil hose or vent discharges from the tanks. 

When filling tanks they should be carefully watched to prevent leaks, atsd should 
such leaks deveJop, the loading most at once cease and steps should be taken to stop 
the leaks without generating excessive heat or causing sparks. 



COMMERCIAL GASOLINE ' 

BY 

FRANK W. STERLING 

All figures relative to boiling point, specific gravity, composition, etc., 
must be comparative, for naturally the product varies with the original crude 
oil. Approximately the range of diitillation temperatures for commercial 
gasoline ia 115 to 350 deg. F. At the lower temperature gasoline is distilled 
off« then, aa the temperature is increased, follow benzine, naphtha and light 
kerosene in the order named. Commercial gasoline may contain any or all 
of these fractions. 

Its specific gravity varies from 0.65 to 0.75, depending upon the propor- 
tions of C and H in its composition, and it weighs about 6.2 lbs. per gal. 
The analysis of an ordinary sample shows approximately C 85 per cent, 
H 14.8 per cent, impurities (principally O) 0.2 per cent. Its net thermal 
▼slue varies with the analysis around 18,000 B.t.u. per lb. 

The ultimate Talue of a gasoline as fuel depends upon its volatility. 
For this reason the popular specific gravity test is not a true criterion. 
For instance a high speed engine needs a light fuel, easily volatilised, while a 
heavy-duty, slow-speed motor can use a much heavier fuel. Were the entire 
supply of gasoline derived from one field, fractions obtained at the same 
temperatures would always have the same composition and hence the same 

^■specific gravity. But, as theworid's supply is obtained from many fields in 
which the compositions vary, it is possible to obtain two gasolines of 
widely dififering specific gravities, which will distil at the same temperature 
and which might be of equal value as fuels. 

The volatility of two gasolines being equal, the heavier is more efficient 
due to the presence of a higher percentage of carbon. To prepare gasoline 
for combustion it must be vaporised by passing air over or through the 

.liquid, of by spraying the liquid into the air by force or suction; this process is 
called carburetion. 

Specifications for Motor Gasoline were adopted by the Committee 
on the standardisation of Petroleum Specifications, U. S. Fuel Administration 
October 2, 1918, as follows: 

Quality. Gasoline to be high grade, refined, and free from water and all 
impurities, and shall have a wapor teiuion not greater than 10 lbs. per sq. 
in. at 100 deg. F., same to be determined in accordance with the current 
** Rules and regulations for the transportation of explosives and other 
dangerous articles by freight *'-par. 1824 (k) as issued by the Interstate 
Commerce Commission. 

Inspection and Tests. Inspection. Before acceptance the gasoline 
will be inspected. Samples of each lot will be taken at random. These 
samples immediately after drawing will be retained in a clean absolutely 
tight closed vessel and a sample for test taken from the mixture in this vessel 
directly into the test vessel. 

277 



278 COMMERCIAL OASOLINE 

Test. One hundred cubic centimeters will be taken m a test sample. The 
apparatus and method of conducting the distillation test shall be that 
described in Bureau of Mines Technical Paper No. 166, Motor Gasoline, 
(a) Boiling point must not be higher than 60 deg. C. (140 deg. F.) 
(6) 20 per cent of the sample must distil below 105 deg. C. (221 deg. F.) 

(c) 46 per cent must distil below 135 deg. C. (275 deg. F.). 

(d) 90 per cent must distil below 180 deg. G. (366 deg. F.). 

(e) The end or dry point of distillation must not be higher than 220 deg. G. 
(428 deg. F.). 

if) Not less than 05 per cent of the liquid will be recovered from the 
distillation. 



COMBUSTION 



PRAHK W. STERLIITG 



I ind S. is the combustible. In muine eu^inMriDg practice. oombuiUbl* 
includni til n»utituaiita of tuel ezoept moiature and asli, thus lacludins the 
and N fuel cantant*. 

PMt*«t Oombuatloa oooun when the mkxinium poaiible unouot of 
tajtai unitea with the oombustible as io the formMkiD of COi. Fartial 
tombat&M takea place whea inoomplet* oxidation occurs, as in the tonna- 
UoDot CO. C and B are the only ohemioal elements of heat value, the siogle 
OMptioii bMog 8, whioh exlata in tuti as an impurity, and which has a 
•mil heat value. 

The ?n>duBts ot Oomplata Oombtudon are correspondingly few in 
Dumber, being COi. HiO. N of the air, and a small amountof sulphur oom- 
poonds that ar« ofteo ignored. 



iiiiuJ wjirLl LkLL J r^ 




Fio. 1. 

Air KCQUirtd for Oombuitlon. Let c. h. and a. denote respectively 
the parts by weight of carbon, hydrogen and oxygen in one lb. of the fuel. 
Then tiie minimum weight of oxygen required for <x>mplet« oombustion is 
11.6|c+3 (h -i.+8)llbs. 

With sir at 62 deg. F. and at atmospheric pressure, the minimum volume 
of sir required is v. - 147 [G+3(A-a + 8)] cu. ft. 

Fig. 1, Curve A, gives the weight of air required to generate 10,000 

B.t.u. with fuels of different H content. The abscissae are the per oeut 

of availabla H per lb. of oombustible. The available H - per oeot H - 

Z7S 



280 COMBUSTION 

percent o + S. Per cent of available H = (per cent H — percent o + 8) -s- 
per cent H. This in commercial coals varies from 2.5 to 5. 

Curve B gives the weight of combustible to generate 10,000 B.t.u. 
To obtain weight of air theoretically required per lb. of fuel, multiply the 
heating value of the fuel by th0 weight of air theoretically required to generate 
10,000 B.t.u., as obtained from the curve, and divide by 10,000. The 
heating value of contained S is disregarded in these curves, its percentage 
being small. 

KzeetB Air. In practice an excess of air over that required for perfect 
combustion is admitted to the furnace. An excess of air is required (1) 
because It is impossible to bring into intimate contact every particle of 
air and combustible due to dilution of the O in the air by K, and because of 
uneven thickness of fires, etc., and (2) because an appreciable time is required 
for combustion according to the law of mass action. With only the theoret- 
ical amount of air present, as combustion pn>ceed5 in a furnace, the mass of 
free oxygen and coriibustible gas will become less and less compared with 
the total mass of gais present and their combustion will become riower until 
it reaches sero. With the present arrangements the reactions will take 
so long that the gases will have pas^d through the furhace before combustion 
is complete, see p. 481. 

 

Losses Dne to Xzeess Air are (1) prodtiots of combvLstion aVe diluted 
and carry off an excessive amount of heat in the smoke pipe, (2) the furnace 
temperature may be so lowered as to retard combustion or cause formation 
of CO (3) torching, that is burning at the smoke pipe top, m.ay be caused 
due to (2). 

Volume Contraction. The water vapor formed by combustion of 
hydrogen condenses at the temperature at which a flue gas analysis is made. 
As the nitrogen that accompanies the oxygen used in the hydrogen combua- 
tion retains its gaseous state, the result of this condensation is to increase 
the apparent percentage of nitrogen in the flue gas. 

Combustion Products. If vm is the minimum volume of air required 
for complete combustion and xnm the actual volume supplied, then the prod- 
ucts will contain per lb. of fuel Oj «-0.21 «„ (» — 1) cu. ft., Ni - 0.79 
xvm cu. ft. 

From the reaction equation C+02sC0i, the volume of COs formed ia 
equal to the volume of oxygen required for the carbon constituent alone; 
hence, volume of CO»-0.21»«c + (c-|-3 (^-0.125o)). 

Of the dry gaseous products (t.«., without water) the COi content by volume 
is therefore given by the expression, 

COi=0.21c +[;cc + (a;-0.21)3(A -0.1250)]. 

The combined COt and Ox content is 

COj+Oi -0.21 { 1 -0.79 -s- [x+cx +3(fc -0.125o) - 0.21]) . 

If the fuel is all carbon the combined COs acui Ot is by volume 21 set cent 
of the gaseous products. The noore hydrogen contained in the fuel the* 
smaller is the COs-fOt content. The CO i content depends in the first 
instance on the excess of air. Thus, for pure carbon it is COs =0.21 -^x. 

The excees of air may be calculated from the composition of the gases anci 

that of the fuel. Thus x = 0.21 ^ -f 3(A -0.125o) +(c-|-3 (A -0.125o)l. 
in which COi denotes the per cent by volume of the COs in the dry gas. 



t ^ 



OIL FUEL BURNING 

BY 

ALBERT M. PENN 

The three fundamental factors which control the proper oombue- 
tion of fuel oil are: fl)the atomixation or the breaking up of the oil into 
minute particles; (2) the introduction of air in just suf&cient quantity and in 
such a manner that it will surround every particle of oil and cause complete 
combustion; and (3) a furnace so constructed that the gases will be kept 
above ignition temperatures until combustion is completed, 

ATOMIZATION 

Prior to the derelopmeat of the atomizere in general um at present, attempts were 
made, with but limited Buoceas, to burn the oil in shallow open pans and modifications 
thereof. This system was only practicable an shore and in very small units. Its 
inefficiency lies primarily in the inability to introduce sufficient air for complete com- 
bustion to the surface of the oil. 

Extensive experimentation in pre-gaslfyillg the oil fuel in auxiliary apparatus before 
its introduction into the furnace has also met with very limited success, though excellent 
Ksulta are obtained with the lighter petroleum distillatee— -naphthas, gasolines and kero- 
senes. In ganfication, the application of heat is essential; the very high temperature 
to which it roust be heated causes a breaking down of fuel oils with the resultant deposit- 
ing of the residuum in the form of sludge and carbon, which soon dogs up the apparatus 
.jiad makes it inoperative. 

I  

; Preeent Methodl of Atomisation are a compromise between the two 
tfystems referred to above. The oil is injected into the furnace in the form 

Sof a spray of finely divided, fog-like particles. The atomisation is aecom- 
plished in three ways. < These are named after the atomising agent used in each 
case: (1) Steam Atomisers; (2) Air Atomisers; (3) Pi'essure or Mechanical 
Atomisers. 

For Marine Purposes, the last named is the only one worthy of serious 
r^nsideration, but the engineer should be acquainted with the principles, 
•tHdvantagee and disadvantages of all three. 

Steam Atomisation is the simplest and is efficient for stationary plants 
c^vliere the water supply is plentiful. The first cost of equipment is low. 
Oil at low pressure is delivered to the atomiser, where it comes in contact 
■-with a jet of dry steam which breaks it up into fine particles. The vapor- 
J ifcs miicture enters the furnace where it is oonsamed. The air for oonibustion 
B|e generally supplied by natural draft. Some claim that the ekpa^eion 
I of the steam, due to its rapid superheating to the high furnace temperature, 
I tends to further atomise the oil and thereby aids combustion. 

PVom H to H of a lb. of steam b required for every pound of cnl fuel. In stBtlonary 

I j prac ti e e this loss of fresh water in the form of steam may be of minor eonaequenee and 

■0 offset by the inereaae in furnace efficiency, but for marine purposes the use of steam 

gm an atomising agent means a serious drain, whether the water used is attained by 

distillation or whether a dead weight of water be carried in the double bottoms. 

281 



071. F 



L BVRNUm 



Oom^MMd Air AtomlHrt oparale on the Mune principle u thow 
luing iteuD. A jet of air at liigh presnir* breaks up the oil. Some typei 
tue air at only a few pounds pressure, but their effident One is limited to 
the lighter grades oi oil. The neoeesary air oompressors mean a high first 
cost. and. on board iliip, encroach upon the weiaht and space given to 
mactunery. Upkeep and power used are alio wrious oonsiderstions. That 
the eompr e ss n d air supplied for atomiUDg purpoaee is far from sufficient 
for oomplete oombustion must not be overlooked. 

Air atomiHrs oooupy an eitensiTe 6eld of usefulness. Tliey are well 
adapted to heat treatiog furoBCee, for annealing, case bardenilig. tempering, 
tool dressing, etc. 



Hmrfactt mariM 
gthrhinluiiiy. 







Fn. 1.— Bureau S. E. type 1 standard pree 

Th* pr«Mun or awchaolwl fttomiaar has practically been unlnriAll] 
Ml^tt*d fcr nurln* boUer tlM. There are many types of pressure atomiseri 
on the market. All inoorporate the principle of fordng oil under high preaaun 
through passages in the atomlier so arranged as to give the oil a high velocity 
of rotation and thus break it up under the action of oentrifugai force. 

The rotation ia aeoomptished in two general ways: in one, the oil is (orosd 
at lugh preeeure through spiral groovee that discharge into a small cylindri- 
cal chamber. The end of this chamber opposite the entering spiral grooves 
is ooned out. At the apex of this cone is the tip orifice through which the 
oil flows in a direction at right angles to tbe rotation given it by the epira] 



ATOUIZSRa 2S3 

groovee. In ths aeoond method, the ToMtion ii aooompUahed bj meani of 
tangentiid groovea or holea diBcbmrginB Into a niMll oylindtiitml ohunber. Th« 
tip end of thia ehunber is ooned out and. m with the spiral type, at the apex 
of thia cone ia the orifice through which the oil is diRcharged. 

 Iha oil leaves ttui oiiSee. in both isoeial typea, it ia Kted on by thne forsei: 
CTKTity^ «atrilnffsl bTtioD, diu to totstioD; and truiilaticui along tba axis of the atom- 
iser. As s result, on lesvins the oriBoe the small streams of oil break up into very iBe 
lo«-like particles. Each particle of oil tenili to Dy olT in s siraicht ling at an scute aocl* 
be axis al the otifiee. and also at an acuu sn^le to ths tangent to thia oriSee at the 
It left by the particle of oil. The path ol each IndiTidual particle ol oil would be a 
Mraicht line as abore, but tor the dowDwsnt eurre. doe to the action ol tnTitx- This 
' s a cone of finely stomised oil. 



OH Dlul»r(*P»»Bn-Ul.MiH.t>.au|. 

Flo. 2. — Frewure-capacity curvee Burean .8. E. typ« I alandard praasure 



Tb« oil eon* should be hoilaw and the wall so thin and uniform that air 
admitted to it can readily mix with the particles ol oil. Atomiiera of 
different deaigoa, but of the lame capacity and making sprayB of the same 
angle, can be quite different io the quality of the sprays produced, depending 
upon how hollow the cone Li, the fineneuol the particles of oil, and thMf degree 
of freedom from streaks. 

There are practical coasiderBtiDnB which make it desirable to keep the 
anfl* of vraj at about 75 deg., such as, the siie of the furnace openings, 
the interference of one Bpray with another, the formation of carbon on the 
boileT tubes and furnace walls. The angle of spray and the fineness of 
■tomisation are affected by: (I) the depth and shape of the orifice walls; 
(2) the Biae and shape of the whiriing chamber: (3) the number of tangential 
slots that direct the oil to the whirKog chamtwr; (4) the angle at which the 
slots are indlned to the axis tA the burner; and (6) the ratio of the oombinad 
eroae-eectional areas of ths tangential slote to the area of ths oriBee. 



2S4 OIL FVSL BURNING 

The pnportlODS ot tlw Twlouf oil punc** » determiiied eipefi- 
meotallr, sod *llcbt Taiifttioiu from h set ataiuUnl have & noticeable 
efteot OD roaults, Where a number a( atDmiieis are Uaed OB a boiler Iroot, 



Srr«y«r Noill* 

Pro- 3. — Peabody prcaBure stomiior. 



w 





J 


ff 


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so 


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100 WD IM I 



. Fio. 4. — PresBurercapaoity curve Peabody prfsaure atoiniier. 

it in MKintial, for affictoot. msnipDlatioB, .that all ptoduee noKorini spraya- 
fUs. regtuNi in maDuraoiiKe Uiat tlka.atwMMri ba aa neadiy uBiforra with 
each other M ilia, tvactioaUyipoonUe^MAtakp Uten. ; n ' 



ATOMIZB/tS 



U ia not ODty aecOHnry tbst (hs vinov 
4Uu b« poLuhed Aod Free Irom blejoishee, 
or mu the poUahed lUif tool. Nub ot 

Copper wire. niBich sUcti or tooth piclu will clean in onnce wimout msrKing ii 
tamoTliK carbon, aoHliiDg with kcroaenE will loosen mogt oF it sod uteel woolm; 
wHh B hardwood stick, properly shAped uid rhueked in > hisfa speed BenaitiTi 
PRO, u gffeetin. Abr«ll*M tliat win wear whirlinc ehunber ar orifloe mnM oi 



Wmt o»p»aitlra b1 



Id In k tMilw M Um 

[B sbould bg tested for ,defe«ta with 







rS 



Flo. 5, — Sohutte-Koertins pressure atomiier. 

TrpM of Tt*nan At«iiti«n. Figs. 1. 3 imd 6 are sentiooal views of 
premtire atomuera o»ed eilensivsly in the NavJ Service. 

Fig. 1 is the Buraau 8. ■. Tj3>a 1 Stutdard kbtnalmtr. It is composed 
o( two part*. 'the tip ftnd th» plug. The tip oontains the orifioe and whirling 
chamlin'. and the plu| the tBngeotial grooves wMch impart the whirling 
niotioD to the oil.' The plue does not revolve but ia held ia place against 
the tip hy the pivsenre of the oil behind it. The proper eombibalion ol, tips 
and plugs and the curv«R of 0Bp»ait7 in each caM are illuDtn^ed in flf. 2t 



285 



OIL FUEL BURNING 



Fig. 3 is ft sectional view of the Peabody Atomlier. In this design 
the orifioe, whirling chamber, and the oil channels are all contained in one 
piece known as the aprayer plate. Suitably drilled holes direct the oil 
to the channels tangent to the whirling chamber. 

In designating Peabody Atomisers the first number indicates the siae 
of the orifice by drill numbers, and the figure following the dash is the ratio 
between the combined areas of the slots and the area of the orifioe. The most 
conmion sises of this tip and their capacity curves are shown in Fig. 4. 

Fig. 5 is a sectional view "Of the Schutte-Koerting Atomlier. This is 
one of the very few atomisers that uses a screw thread to cause rotation of the 
oil just prior to its exit through the orifice. This icrew has a triple thread 
which fits in the tip with a vexy little clearance, and is kept from rotating 
by a square shank which fits in a socket in the base of the atomiser. The 



260 



cr») 



s 





9 
U 

m 



uo 



100 



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r / / / / / 


1 I 1 I J f / 


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SI si m Si / j» ' ' 

r/ ^i m W w fy y 


~^f V *>7 V V ^/ J/ 


JIL t Jr T I W- 


t 4-4 7 -/ V -.^ 


Til// / Oii.«^a.^/ 


^ i I 1 / Wion.iiAfcW^fifi* ■•i^'l' 




1 t t 1 J V ^2 =ii^^3^ 


... t ri t . r / 7 ^mrVn 



§ § § §':$ 

PouDda OU Per Hoar 

Fio. 6. — Piressure-capacity curve Schutte-Koerting pressure atomiser. 



sizes of the Schutte-Koerting tips are designated by the diameter in milli- 
meters of the hole in the tip. They are made in a number of sises begin- 
ning with 1 mm. On destroyers a 1-mm. tip is the sise usually used in 
port and 2.3 mm. at sea. Battleships generally use the 1.5 to 1.7 mm. sises. 
The various sizes and their rated capacity are shown in Fig. 6. 

Effect of Heating OU. With the pressure or mechanical systems. 
fuel oil is heated for the lole purpose of reducinir the Tlacosity, or, 
in other words, increasing the fluidity. This is eesential, primarily as an 
aid to fineness of atomization, but, occasionally, with extremely viscous 
oils at low temperatures, some heating is neoeesary to reduce the viscosity 
so that the pumps may handle the oil at full capacity. This viscosity 
necessarily depends on the type of pumps used. 

Of primary importance to the operating engineer is the reQuilite ?isoosity 
to obtain the best atomisation. The extent to which an oil may be 
atomized is not alone dependent upon the design of the atomiser but upon 
the viscosity of the oil as well. The thinner the oil the finer will be the 
atomization produced. The greater the viscosity, the more difficult it 



AIB FOR COMBUSTION 287 

becomes for the atomLser to break up the oil into particles fine enough for its 
intimate mixture with the necessary air for combustion. Where viscous oils ^ 
are used .this is a difficulty which the pressure atomiser of itself is unable to ' 
overcome. 

The curves in Figs. 7 and 7a show graphically the effect of heating on the 
viseoeity of fuel oils. It will be observed that, for those oils having a gravity 
Baum6 of 20 (sp. gr. 0.9340) and above, very little reduction in viscosity is 
gained by heating above 130 deg. F. Inasmuch as pressure atomisers will pro- 
duce efficient atomisation with oils at a viscosity between 2 deg. and 4 deg. 
£ngler (75 and 150 Saybolt sec.) there is no practical gain in heating the oil 
above the temperature that will give a viscosity between these limits. 

In the ease of the more ▼iscons oQs, it is neither desirable nor practicable to reduce 
the viflcoaity to ao low a point, aa to do so would require heatinc the oil to a temperature 
high above the flash point; a dangerous expedient unloes extreme care is taken to guard 
against leaks in the oil Knes. With some very viscous oils, having a low flash point, 
it will be necessary to ignore this precaution in order that the viscosity may be reduced 
to that required for moderately good atomisation. With these oils, that temperature 
which win i^ve a viscosity of about 8 deg. Engler (300 Saybolt sec.), or slightly lower, 
is sufficient to give satisfactory combustion in a boiler furnace. A lower viscosity would 
afford finer atomisation. and consequently more rapid and efficient combustion, which, 
incidentally, would permit of a greater rate of combustion per cu. ft. of furnace volume 
per hour. In addition to the obiections dted to the heating of a very viscous oil to 
excessive temperatures, may be added the large extra weight and space required for oil 
heaters of sufficient capacity, and also the danger of breaking down the oil, eausing 
it to clog up the heaters and oil lines and to carbonise the atomising tip. 

AIB rOB COMBUSTION 

Azmrant of air theoretically required for complete combustion of fuel 
oil varies with its chemical composition. Under " Boiler Tests," page 480 
I are the neceesary formulae for calculating exactly the amount required. 

For average fuel oils, the amount of air theoretically required varies between 
18.8 and 14.4 Ibt. par lb. of fuel, or, expressed in cu. ft. from 180 to 
200 per lb. of fuel. 

In practice, the efficiency of combustion may be considered very good 
if the azcoM air is kept below 30 per cent, and excellent if below 10 per cent. 
On boiler evaporative tests conducted under the most favorable conditions 
the ezoeflB air has been reduced to as low as 4 and 5 per cent, but this is ex- 
ceptional. Percentages of excess air as high as 200 per cent are of common 
occurrence. It is the most lerlous and most common cause of low 
fumaea offldonej. 

The aid of a gas analysis apparatus, described on p. 483, is essential 
to reduce excess air to a minimum. A study of the appearance of the furnace 
is also of valuable assistance. If the flame is an incandescent white and the 
furnace walls are dearly discernible through it, there is considerable excess 
air present. 

As the percentage of excess air is reduced, the color of the flame at the rear of the 
furnace becomes a pale yellow, then yellowish orange and orange red. In general, with 
an efficient installation operating under a minimum of excess air, the ends of the flame 
farthest from the atomisers are a yellowish orange or golden shade. The gases of com- 
bastion are colorless and the seams in the brick arc just discernible. 

At very high rates of oombustion, when the flame completely fills the furnace, the 
very high furnace temperatures preclude the presence of these temperature colors. An 
ineandesoent and dassHng white still indicates excess air but a reduction in this excess 
is only indicated in the furnace by a softening in the intensity of the white flame. 



r, FirET. BVR.MXO 



WkmIUc* Eoglcr Compared with Water U 7a Fahrenheit - i 
FiQ. 7.— Tempcratur 



TBMPERATURE-ViaCOaiTY fVRVBS 289 

L. SU>rCalil<irmi,23.9d«.B«uin^ tSOdcK. F.fluh. 

' "SUndud" lodiaba. 24.6 dec. Baumi, 144 ilcg. F. fluh. 
Sundud" Ulinoia, 27 .S d«. Baumi, 146 d(«. F. tluh. 
!un CompKOT'i Lmiaiau. 10.S Bbuiii& 275 deg. F. fluli. 
Avon Refinery" AwKinlcd Oil Co.. CsUI.. [7.1 dec. Baunifi, lOS dec. F. Hul 
Coslinc* Field" AHoc>«I«d Oil Co., Monterey, CJif., 16.3 dea. Baumt. IBS o 



TO 1G 8D BE » % 100 105 110 lis lag 1Z& 130 
VlKoiltlet Ensler Compared with Watat at TDFabicnhelt ' I 
!■ of hpavf gndee of oili. 



OIL FUEL BURNim 



VUcMltiM Eoiltr Compared with Water at 7o'Fahi«ihdt - I 
Tta. 7a. — Temp«n>tiira Taoodty ourrea of light sradea of (As. 



CONTHOL AIR RtOtSTSRS 



Fio. 8. — Buieau S. E. type 2 stanilard forced draft tur oontrol ngtster. 









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1.0 1.1 LI LI 



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ilii 
llli 



292 OIL FUSL BURNING 

A perfectly eleu unoke pipa ia deceiving; it nay meiui only a sipall 
amount of eicosa air, or it may mean as much as 300 per ceut excess. Acleu 
■moke plpa U id«^ whsn Uie gas Mulyili kt the suaa time alMnrs 
hl|b COt, vary low Oj uid do CO; for axAmple, 14.7 per cent COi. 0.8 

per cent Ot, 0.0 per cent CO. 

Under the ulukl operatlnc condltloni in marine service, it is good 
practice to require the fire room personnel to reduce the supply of air until 
a Torj light brown haia is emitted from the smoke pipe. This aasumea 
that dirty or streaky alomizen! have been eliminated, and that the installation 
when properly operated is efficient. 

It ie well to remember that the prMsnca of ttnok* does not always 
mean insufficient air or high CO. An inefficient installation, poor atomiia- 
tion, poor mixture ol air aud oil, unconsumed oil striking cooling surfaces, 
and poorly designed furnace, (requeutly cause smoke wbea the air supplied 
for combustion may be far in ezceaa of that required. 



\,.i-f] 



Leftki In boilor caiingi are a serious source ot excess air. This air 
does not become intimately mixed with the fuel and every efFort should be 
made to keep boiler casings tight. Air leaking through casings not only 
does not aid in further combUBtion oF unburoed gases, but also has a chilling 
eRect on both the gases of combustion and the heating surfaces. Loss of 
boiler efficiency due to thia cause-may amount to 10 per cent m more and 
increases as the draft increases. 

Air Control Eeclaten. With the pressuro or mechanical system, the 
most importaat part of the installation Is the air register or tuyere. ThS 
purpoas of the air register is to so introduce the air supplied for oorabustion 
that it penetrates the oil spray and becomes tboroughty mixed therewith 
in the proper proportion. This must be accomplished wilb a minimum of 



AIR CONTROL RBQISTERS 



293 



dotad yire Boom, in which the air is /oroed into an air-tight fire room by 
forced draft fan blowers; (2) the Howdan System, in which the air for combus- 
tion is forced by blowers through air ducts to an air-tight box casing on the 



«( 86 

I" 

N 



I 



19 



I « 

8M 
■• TOO 

I ^ 

I 300 
I 400 

no 











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Sqtt 


ItiUbI 


Xvttpo 


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of Oil 


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,12 



.IB 
•rou 



.20 .24 .28 .32 

par Bf^ft, tt iTMlcf UcdUbx 8«uteM > Lta^par lUw 

Fio. 11. 








.3 .4 

•CM 



.& .0 .7 .8 
pM S4. ''U of Wtiar 

Fig. 12. 



1.1 1.2 

irBvar. 



furnace front; (3) N^turiU Draft, in which the haight of smoke pipe is 
relied upon to induce a sufficient flow of air into the furnace; and (4) Induced 
Praf t, in which blowers are installed in the uptake or smoke pipe to produce a 



291 OIL FUEL BVRNISa 

■action from (he fiutiaoa and to drive the gases of combustion ont of ti)e tmoke 
pipe. 

Tbe foUoiriDK is a partial UU of air rcBlBters that wOl be met with in Marine 

Bailey Rigutcr and fiurtwi— mauufKctursd by Ncirpon Nan 8. B. k D. D. Co 

Coen It<ci>l«r mA Burixi — maaulMtured by The Coan Co. 

Dabl Rtsiiler and Burngi — m>nu(Htiir«il by Union Iron Worki. 

Fore River Reciitar and Buraei — manulaalund by Fore River 8. B. Corp. 




Fia. 13.— Peabody air control resister. 



Fra. 14. 

Mooie and Boott R«^at«i and Burner— manutaMured by Moore ABeott Iron Wotka. 

Normand Reiiater and Buinei — niBnufactured by Bath Iron Work*. 
Peabody RegUt^r «nd Burnei— m«nufactured by Babcook * Wilcoi Co. 
Sohutte-Kocrting Register and Burner- msDut act ured by Bohutte A KoarUag Co. 
The Wbits Syatem— manufactured by The Waahincton EnaiM Woika. 
The Tat^nlonee 8yitem'-nianufaalured by The Tate-Joaei Co. 
Bureau <^ Steam EnciDeerioi'B Staodaid Isstatlationa, 



AIB CONTROL^ 

Ttp«B of Air KaglatMl. The fiva ur-oODtrolliDB reclatera iUmtrated 
hnekflcir bring out tb* geoenJ eharocteriatica of all reguton usmI with 
preamn >tomiaen on ablpboaid. 




FIc- S ahowi the But*»u of S.  Tjpe S Btuid»rd Toread Draft Ek^ 
tar, with the Bunau Stsodftrd Atomiter properly loc&t«d. After a saries 
of teat* eonduoted on the Experimental Wbitv-Fomter boiler at tb* 



306 OIL PVKL BVUmKO 

Natal Pvd M Tettifig Fiant, Philadelphia, thia nglitM ftnd Btomiwr nero 
adopted by the Bureau of Steam EngiiMering as the standard high'power 
deBtroyer mat&llHtion. Fig. 9 is a set oE curves showing the ratulU of thcM 

Fig. 10 'shows the Buraftu of .S. ■. Typ* 1 St(Uld*rd HatunJ-rorcad 
Draft EaffUtsr, bb developed at the A'ovaJ Fuel Oil TaUng Plant. It was 
especially designed for efGoient operation under natur^ draft and at bw 
poirerB. but it can readily be forsed to high rates of combustion. This regis- 
ter baa been adopted by the Bureau of S, E. for battleships tuid auxiliary ahipn 
of moderate power. It has been installed on a few destroyeis where it has 
^ven very satisfactory results at high poweie. Fig. 11 is a set of curves show- 
ing the results of eTAporfttlva teita under nkturftl draft using thia regialer 
on a Babcock A. Wilooi oil-buming boiler uf the type installed on the Battle- 
ships OktiJwma and Penjayhania. Fig. 12 is a set of curves showing the 
results of t«ats UBdar hifh power at forced draft with this reKist«r iastalled 
on the experimental White-Forster boiler at the Fud Oil Tealing PUnU. 



Fro. 16.— Schutte-Koerting s 

Fig. 1.1 shorn the latest type Paabodj EagUter RtttA with the Peabody 
Atomiier asmanufactursd by theBobcoct ifc Wilcox Comfiany. It is installed 

on the Bftttleshipa New Merieo and Miteiinppi and on numerous vessels 
of other types, both in the Nai-y and in the Merohant Marine. This 
register was designed to operate under natural draft and at moderate powers, 
but may be readily and'eiEBciently forced to high rates of oombustion> Fig. 
14 ia a set of curves showing the results of tests conducted on the experi- 
mental White-Forster boiler installed at the Fuel Oil TesKnu Plant with this 
installation. 

Fig 15 illustrates the DaM Air Control K«giat«r, manufactured by the 
(/num. /ran Works, installed on the funiape of a Scotch boiler. This system 
is a low pow^r, low draft type eiten^vely used in the merohant marine on 
the Pacific Coast. 



BOILER FURNACE DESIGN 297 

The Sehutte-Koerthig Air Bafister and Burner as manufactured 
by the Schutte &■ Koerting Company is illustrated in Fig. 16. This installa- 
tion is esaentially a high-forced draft system. It was extensively used in the 
Naval Servioe on deetroyers and other vessels some six years ago. 

BOILER rUBKACI DSSiaiT 

The shape, else and materials of oonstruotion of the marine boiler 
furnace have a very decided influence on both the furnace efficiency and 
the ralw of combustion when oil is used as the fuel. The ideal furnace 
would have the following characteristics: (1) Sufficient furnace volume 
for total oil burned at the designed rate oi combustion; (2) the maximum 
of refractory surface to assist in maintaining a high furnace temperature; 
(3) increase of cross-sectional area of the furnace with the expcuision of the 
gases; (4) minimum area of cooling surfaces close to the flame, tending 
to reduce the furnace temperature; (5) walls and tubes just sufficiently 
remote from burners to permit of cohiplete combustion of oil before coming 
in contact with them; (6) a minimum of infiltration of air except through 
the air controlling registers provided for the purpose; (7) exit from furnace 
of incandescent gases of completed combustion at a maximum distance 
from the burner. 

The design of the marine boiler, and the various structural limitations, 
such as economy in weight and space, preclude complying fully with all of the 
above requirements. 

The different tjrpes of oil-burning furnaces may be classified for 
marine purposes as follows: (1) flue furnaces; (2) Tube-roofed furnaces; and 
(3) Triangular section, inclined tube-sided, furnaces. 

In the Scotch Boiler the length of the furnace flue and the combustion 
chamber provided are favorable features of this type, but perhaps the main 
advantage that can be claimed is the elimination of flame interference between 
adjacent burners by the use of only one burner per furnace. The close 
proximity of cooling surfaces and the difficulty experienced with circular 
refractory linings are the most serious objections. 

The Baboock & Wilcox marine boiler is an excellent example of the large 
tubo-roofed furnace. The general shape of the furnace, the increasing 
volume for the expanding gases* the large incandescent refractory surface 
which tends to maintain, a high furnace temperature, and the location of 
the exit to the gas pass through the tubes; all tend to make this furnace 
ideal for the purpose. 

The furnaces of all boilers having furnaces of class 3 type are very similar 
in shape and sixe and are such as exist in all boilers of the well known 
"Sspress Type. ' ' The furnace exit to the gas passes of the Normand boiler is 
different from the others of this type in that the gases of combustion can 
enter the tube banks at onelend. Insofar as this arrangement affects furnace 
eflicieifecy, it is an excellent design where entry occurs at the rear end. 

riTBNACX INSULATION 

Radiation of heat from the furnace walls is taken care of in two ways 
in the marine installation; either by circulating air over the radiating surface, 
and in this way carrying off the heat, or by backing the refractory lining up 
with a good insulating material and thereby keeping the heat in the furnace. 
The method of circulating air b used in destroyer installations where weight 
and space do not permit the use of thick refractory walls backed by several 
inches of insulation. A light metal outer casing open at the bottom and top 
forms an air space. Air flowing up through this space carries off the radiant 



ZivO 



OIL FUEL BURNING 



heat into the fire room where it finds ite way into the furnace through the 
air registerB or is dissipated through the ship's side to the water. 

Such an arrangement is not permissible on large ships with double bottoms 
as the heat banks up in the fire rooms and makes them untenable for the per- 
sonnel; to avoid this the heat is kept in the furnace by the use of insulation. 

In low-powered installations, common to auxiliary ships of the Navy and 
the Merchant Marine, the question of insulation involves no serious 
difficulties. Nine inch brick walls backed by about 4 in. of an improved insula- 
tion is satisfactory. But in the case of high-powered light-weight installt^ 
tions, such as battle cruisers and scout cruisers the problem becomes more 
serious. A 4 or 4>i-in- brick wall is the maximum limit for refractory 




A.Mt-* 



9HX) lOiOe IS :00 240 4.'00 6:00 8:00 lOiOO U :00 2«1N) 4:00 0:00 8^00 lO-'OO 



-P.M; 



TIm« 



-A.Mt- 



Fio. 17. 



lining. This must be backed by a superior high-heat insulation. The 
insulation problem is constantly under investigation and the set of curves 
in Fig. 17 provide some interesting data on this subject. 

The furnace used for testing insulation was designed to simulate, as closely 
as possible, service conditions in the furnaces of high-powered, marine oil- 
burning boilers. A 4V^-in. refractory lining is backed by 3 in. of insulation 
in two layers of if^-in. thickness. This is in turn backed by the usual 
metal furnace casing. 

The test is essentially a comparative servioe test between two grades of insulsUon. 
Curve F is the furnace temp^sture. Curves Am and B» represent the temperatures 
through the 4H-in. refractory brick wall on each side of the furnace, taken between 
the brick and insulation A on one side and between the brick and insulation B on the 
other side. They are the temperatures to which the inner surfaces of the two insulations 
were exposed. 

Curves A^ and B^ are the temperatures meaeured through the inner WiAn. layers 
of the two insulations. 

Curves A a and Bt are the temperatures meaeured through the 3-in. thickness of the 
two insulations. 

Curve R is the room temperature measured 6 inches away from the |petal side oadags. 

A study of these curves combined with other characteristics such as shrinkage, loas 
in weight, etc., determines the superiority of one or the other. 



INSULATION 299 

The more oommon insulatUur inaUriAlB we not aatiaf aotoiy as a furnace 
refractory backing, especially in the high powered light weight installations. 

Two to four inches of bloek UMgnaiia protected by }^ in. asbestos mill- 
board was common practice until recent years. Though both are excellent 
insulations at usual temperatures, they are unable to withstand the extreme 
furnace conditions peculiar to oil burning marine high powered boilers. The 
ai^ostoi boftrd soon Titriflet and loses its insulating value at the high 
temperatures to which it is subjected. The bloek magnesia, in time, com- 
pletely diiinteCTatM, becoming a fine powder and losing all its insulating 
characteristics. 

The most Mbtitf aetory iniulAtinff materialt on the market for furnace 
linings are made from dlatomaeeoui •arth (otherwise known as "infuso- 
rial," ** Kielsilguhr," "fossil meal," and "celite"), a mineral of minute cellu- 
lar structure and of almost pure silicious composition. In the raw state as 
mined, it is an excellent insulation at moderately high temperatures, but is 
subject to excessive shrinkage at temperatures above- 1600 deg. F. (871 deg. 
C.) ; this soon destrojrs the insulating qualities. 

By ealdiiizig, the shrinkage is reduced and the material is made available 
for use as a high temperature insulation, and though this process increases 
the weight and tends to reduce the insulating value, nevertheless, it reduces 
the tendency to spall and disintegrate at higher temperatures. The use of 
carbonates, such as calcium carbonate, as a bonding material is common 
practice. This is objectionable as the carbonates cause spalling. Their 
presence can be detected by testing with hydrochloric acid. 

The raw diatomaceous earth may be procured as mined in powdered or 
brick form, also combined with bonding material in plastic or block form. 
Calcined, it may be obtained pure as a powder and in lump or, combined 
with bonds, in plastic and block form. 

Calcined to about 2100 deg. F. (1149 deg. C.) then bonded together with 
silicates and long fibre asbestos into a compact block, diatomaceous earth 
is probably the best material for use as an insulation backing to the refractory 
lining of high powered oil burning boiler furnaces. 

In its present state of development, the calcined diatomaceous earth in 
block form is heavier than desirable but there is every assurance that this 
objection will soon be overcome and a much improved high heat insulation 
developed. 

For faiwilating mat«rialft on the market, made from diatomaceous earth, 
both raw as mined and calcined, see p. 439. 

RXLATIOH8 BSTWSSH RATS OF OOMBtTSTION, HSATUfG 
SUBTACC, FtTENACI VOLtTBOB AHD AIE PBB8ftUBE 

The rate of combuition of an oil burning boiler is expressed in the amount 
of oil tmnied p«r Mkch »q. ft. of beating turf ac« per hour when the 
eapaoity of the boiler as a generating unit is considered. Closely related 
to this and bearing directly on furnace efficiency is the rate of combustion 
as expressed in Ibt. of oil burned per cu. ft. of Yumac« Volume per hr. 

Esqierience has demonstrated that for design purposes, when the small 
tttbo oxpreM type marine boiler is to be used as in destroyers, scout and 
battle eruisera, 1 lb. of oil may be burned for each sq. ft. of heating surface 
provided though this is frequently exceeded. On a recent test conducted at 
the Naval Fuel Oil Testing Plant, 1.5 lbs. of oil per sq. ft. of H. S. was ex- 
ceeded with a resultant evaporation of slightly better than 24 lbs. of water 
per tQ. ft. of H. S. 



300 



OIL FUEL BURNING 



For the \MXgB tube boiler extensively used on battlesliips, auxiliaries 
and merchant ships, this maximum ratio is 0.75 lb. per sq. ft. In the case 
of merchant ships this is generally reduced to about 0.6. 

In Naval practice experience has shown that the sise of the furnace should 
be sufficient to allow at least 1 cu. ft. of F.V. for every 10.8 lbs. of oil burned 
per hour. In merchant practice this would generally be increased to 1 cu. ft. 
for every 5 lbs. of oil. 

With Scotch Boilers, since the rate of combustion is generally relatively 
tow, 0.5 lb. per sq. ft. of heating surface may be conndered a maximum. 
The furnace volume may be given little consideration as it is generally much 
in excess of that required for the usual rate of combustion. 

The figures given above for F.V. are irequently exceeded, there l)eiiLg 
records of better than 13 lbs. of oil per hour per ou. ft. The rate of coznbue- 



u 







a 

■S 

». 

£ 



8 



7 - 

















. 






/ 




Cum 2to.l — QtfUuU avB^ «t Bamn[ 11) IbmnaIm 
tUir CHMity for IJwnMli« Bate of CootbiMtfan 




... r> 


/j 


/ 


Curr* NobS — The mbm u Cam V^l axMpt aoly 




®<. 


/. 


/ 


y^: 


dim AM ^ VwDWHit sj^ymmKj ^mt Duatr . 




• 


/ 


1\ 


/ 
















5- 


^ 

1 




/ 


- - 










y^ 


^ 


^. ,_ 


y\ 


Y 








X 


^ 


^ 




y 


/ 




— 














^ 


^ 














m 






' 







.1 .1 .3 .4 .3 .C .7 .8 .9 1.0 1.1 1.2 
Oil Burned per 8q.Ft.of Watar H«»llng Sarraee- Founds p«r Hdor 

PlO. 18. 



• I 



tion per eu. f t. of F*V. Cor. Miy fivea boilw in<UbiUlj»tion^ i| ; inipvey ed 
by the heat value of the oU> the i^ presfture, the desigii of air con- 
trolling register and the capacity, number and efficiency of the ato- 
misen or to-called burners. 

The air ^pressure ayaHable has quite a decMed iatfluenee on the rate 
of combiistion as will be observed by reference to the fire-room sxr-pressore 
curves illustrated in Figs. 9, 12 and 14. In each series of tests the curve is 
practically a straight line. Comparing these curves to those showing the 
oil burned per cu. ft. of F.V., which are also straight lines, it will be obaerred 
that the rate of combustion in pounds increases more rapidly than th^ 
corresponding increase of air pressure in inches. From this it is possible to 
predict the air pressure required for increased rate of combustion 
obtained by increasing the number of burners, the capacity of the individual 
burner remaining the same: The above does not apiply where the number 
of burners remains the same and their capacity individually is increased. 



FUEL OIL EQVIPMBNT 



301 



Fig. 18, curves 1 and 2, jdve the approximate slope to the curves rtf the 
fixe-room air pressure plotted against rate of combustion in the case where 
the number of atomizers remains the same and the rate of combustion is 
increased by increasing individual burner capacity. 

Curve 3, Fig. 18, shows the slope to the curve of increasing fire^room air 
pressure as the rate of combustion is increased by increasing the number of 
burners in operation, the capacity of the individuaV burners i^maining 
constant. 

It will be observed that the inor^ase in air preBsure as the rate of combustion is in- 
OT«ased is more rapid in the case where the number of burners remains the same and 
their capacity is increased. If other conditions, such as extent of furnace front, permit, 
higher efficiency and lower air pressures will be attained when the rate of combttstion is 
increased by increasing the number of atomisers in operation instead of increasing the 
capacity of the individual atomisers. 



|4 

IF 

I 

1 s 



























r^KHMM Pr«Mnm on Kxpuimen 
HntriocMn 6tk Buak* Bolkr 1 
Vtrlnu lypM oC Alt 0wln4 A^ 


it* 


. 










<s< 




PUEl Olk TESTING PLANT 






s<- 


Ug^-" 




>r' 


tW 








• 












-^ 















.2 .3 .4 .5 .6 .1 .8 .9 1.0 11 12 
Oil Burwd ptc 8f HM WaUr BmIIki tBrfMePoundf p«r flottr 

Fig. 19! 



Fig. 19 illustrates a curve of furnace pressures plotted against rates 
of combustion, for the White-Forster Boiler. This curve is applicable 
to this boiler regardless of the type of oil-burning installation, provided the 
furnace efficiency in each case is the same. A cwve of this type may be 
pl5tted for any given boiler by measuring the furnace pressure at different 
latea of combustion when the gas analysis is practically the same in each 
case. Once this curye is obtained, the ooerating personnel can be' required 
to regulate the fire-room air pressure to maintain the furnace pressure required 
for any particular rate of combustion. The slight variations in the furnace 
pirensure due to atmospheric conditions are negligible. 

This method of air control is a refinement that may never be attained on 
riiip board, but its discussion lends an understanding to the study of efficient 
furnace oombustion. 



rtJSL OIL IQUIPIOMT 



On Xaval vessels the main oil storage tanks are Usually placed both 
forward of the fire rooms and aft of the engine rooms. The distribution 
of weights is generally such that the greatest number of tank^ will be foeud 
forward. In some types of ships additional oil tanks are loetit^d in -the 
double bottoms under engine-room compartTnients. ' 

From the bottom of each forward storage tank a pipe is led to the suction 
and fllllnir manifold in the forward fire-room. A similar manifold is pro- 



302 OIL FUEL BURIUNQ 

vided in the engine room and connected to pipes from the after group of 
storage tanks. The ends of all suction pipes are located about 4 in. from 
bottom of tanks and are fitted with heating coils. Drains from these coils 
lead to an inspection tank. 

From each of the above-mentioned manifolds a combined suction and 
discharge pipe runs to the combined suction and discharge manifold at 
each booitar pump. This pump, of which there is one or more in each 
fire room, takes it suction from this manifold through a duplex strainer 
and discharges through an additional strainer into the oil service pimip 
suction or, as in case of some of the larger ships, discharges into a main form- 
ing a continuous loop common tb all fire rooms and from which all oil seirioe 
pumps take their suction. 

These service pumps, of which there are at least two in each fire room, 
supply the oil through another strainer to the oil fuel heater, thence by way 
of the burner line to the burners. In most cases all the oil service pumpa 
can also take suction direct, without the use of the booster pumps. Both 
fuel oU heaters and strainers can be by-passed. 

For raising steam with no sotirce of power available, a hand pump is 
provided in each fire room. This pump is of suitable size to give a pressure 
of at least 200 lb. on two or more burners. Frequently the discharge from the 
hand pump passes through a eharcoal heater. 

Air banks are placed on the discharge manifold between the two oil 
service pumps, and either between the cut-out valve and the first burner 
or on the extreme end of the burner line. Small connections are installed for 
charging air banks with compressed air. 

The cut-out TalTOS to the burner lines across boiler fronts are fitted with 
extension stems for emergency operation from the deck above. These valves 
are usually of the plug valve type. 

Suitable deck connections and filling lines are installed for filling all 
oil tanks through the combined fuel oil suction and discharge piping. la 
addition, the centre tanks may be filled through the top manhole plates and 
the oil sluiced to the side tanks. Oil may be equalised in the different 
storage tanks through the combined suction and discharge manifolds in 
forward engine room and in after fire rooms. 

The Booster Pumps frequently have a suction connection from the filling 
pipes and can discharge through manifolds to any fuel oil storage tank. They 
are fitted with an overboard discharge connection for the purpose of cleaning 
tanks and for pumping water and sediment from tanks. A section in this 
line is generally made removable to avoid any ];>ossibility of accidentally 
pumping oil overboard. • 

In general, the installation on oil-burning L.erchant ships confoms to 
Naval Practice. On these vessels the suction and filling piping is also used 
for oil ballast and trimming. Instead of air banks being placed on the burner 
line, a large air tank is frequently installed between the service-pump dis- 
charge strainers and the oil fuel heater. The main oil manifolds have steam 
connections for steaming out oil lines and tanks. A return connection to the 
oil service pump suction is provided for the purpose of circulating the oil 
through the burner supply line when first lighting up. 

Pumps. The n^ost common type met with in service is the reciprocating 
piston pump, both single and duplex, but there is now a decided tendency 
toward the use of the rotating plunger and the screw types. The main 
advantage of the latter two types is that they deliver the oil to the atomisers 
at a* steady pressure, while the reciprocating pump requires the fitting of 



FUEL OIL BQVIPMBNT 303 

■ir banka to otishion and absorb the pulaations imparted to the oO on every 
stroke. 

Piston Type Oil Fumps. The following comments on the piaton type 
oil pump were written by Mr, W. A, J9&«en, of the IrUertwHimal Steam Pump 
Co.. and pubUahed in " Oa Fud " by Mr, B. H, Peabody: 

"The pumpB designed, and usuAlly preferred, for handling crude or fuel oils are of 

the duplei piston patteom, except f<v large oapacitiee aooompanied by heary pressure, 

j where an outaids-packsd plunger pump ia to be recommended. 

I "With the iHSton pump there ia only one email stuffing box for the piaton rod. so that 

I the opportunity for leakage, with its resulting danger of fire, U> reduced to a minimum. 

With an outoide-packed plunger pump, there is more or lees drip or leakage from the 

Isiie stuffing boxes. 

"The handling of higli-graTtty fuel oils, running from 90° Baumft up, and quite 
Sqiiid in consistency* ia usually best accomplished by the use of an ordinary duplex 
pump fitted with brass ring packing in the pump pistons and brass valves and special 
ol-proof gaskets in the pump cylinder jcunts to overcome the BolTSnt action of the oU. 
For heavy viscous oil, like Mexican crude, the ordinary duplex piston pump is suitable, 
isorided a sise sufficiently large is selected to keep down the oil velocities through 
the ports and passages and valve seats in the pump cylinders to a minimum. For ideal 
amditaons, the velocity through the vnlye seats should not exceed a speed of 100 ft. 
per min. for pumps of large capacity, and about half of this for small pumps. For Uffht 
flflt around 40° Baum6 the above velocities can be doubled. 

"The type of pump ordinarily used for pumping fuel oU to burners, where the oil 
pnenire will not exceed 160 ibs. persq. in., ia a pump similar to the Snow Duplex piston- 
psttem pump. In selecting this type for. low gravity oila, it ia advisable to use nothing 
■naUer than a"* 4H-in.X2H-inX4-in. sise, aa the ports and valve passages in ami^ 
pomps are too restricted to operate successfully with oils of this character, and it might 
be veil to remember that the 4-in., &-in., and 6-in. stroke duplex fuel oil pumps have vdive 
snaa equivalent to 35 to 40 per cent of the piston area and should operate at speeds, 
■sji not to exceed 30 to 40 single strokes per min. each piaton, and 10-in. and 12-itt 
stroke pumps 25 to 30 single strokes. Fw example, take the 0-in. X 4-in. X 6-in. sise 
operating at 30 strokes— ^is would repreeent a piaton speed of 16 ft. per min., and the 
■Milting speed ci the oil through the valves will be about 40 ft. per min., which is well 
siUun the Umlt. 

"These pumps are very often set in duplicate on a east-iron stand with an ofl heater, 
ihainers, by-pass valves, thermometers, gages, etc., as a Fuel Oil Pumping System. 

"With thia arrangement one pump ia operative and the other is a reserve. A 
J^MSure govetucr or regulator ia aet for the oil pressure and controls the pump auto- 
matieally. Theae systems are usually used in connection with low pressure burners of 
As steam or air atomising type. In rare instances, the single cylinder pump is used, 
shhongh in this country the duplex pump is favored. 

"For high pressure fuel oU systems it is necessary to use pumps designed for 
OfHrating againat oil pressures up to 200 lbs. per sq. in. For horisontal work, the duplex- 
pattern pump of the valve-plate style makes a very efficient and satisfactory pump 
^ the service. For Naval installationa or for marine work where floor space is limited, 
the Tsrtleal duplex Admiralty pump attached to the bulkhead ia usually employed. 
"Hiis t]rpe of pump is good for 300 lbs. maximum oil pressure. 

The same remarks made above with reference to the selection of the sise and capacity 
ef the pump, apply to the high pressure pumpe. 

*Tbe duplex fuel oil pump has been universally regarded as the standard in the 
Oaited Statea, while in England, for Admiralty purpoeee, they oocaatonally use vertical 
■implex pumps, which, if properly fitted up with suction air chamber and discharge air 
chamber, will give almost as steady and conatant a flow of oil as the duplex pump. 

"The slmplez pump, both of the horisontal and vertical type, has better suction 
Qoafitiea than the duplex. The former are usually made longer stroke and permit the 
ase of half the number of valves, which necessarily have to be of larger diameter than 
in the duplex pumpe, and consequently are more favorable for the flow of heavy, viacous 
oiIb. On board ship where the bottom of the fuel oil tanks is plaoed below the location 
of the pump, the simplex pump, with ita better suction qualitiea, will drain the tank 
ia a more aatisfaetory mmnnw than a duplex pump. A auction air chamber should 



OILI'VKL UVH 



txe Iba Sow poH directly into Ihe Buctioa opfning of ihe pump. 
"The pump tU • Mrrlcw oniinKrily lhoI in Fuel oil pump* is the plain bnnw* 
ilvD Bprinji lokded or vith  irlnff'^uidad briHU« vkIvb; tb« Utt«r is uied iz 
aow J^vy prCMiufl pat(«rn uui in th« BJkkfl vortical duplex Admiralty pump. 



hmve adopt^i double- uid qiiftdrupla-bBat 

(Klvai. which pampo have only one valve ppf 

n-ith a. very law liTt. A vaIvo of thii Iyp« 
win ftive full paaBagevray (hrough tha valve \ 
diaca. sa would bn ordiuarily the can »ith^ 
 diK valve, thiu oeeeautating high lilt; thsF 



tual oil pumpi, there is some diversity of 

opinion, but the Qrdinsry eonatruction for Fio. 20. 

■Mtionarr Mnrlra is to inataU pumpa 



I. fitted with 



handling crud* oili coutaliUug cooaidetiblt lulpbur,  

aideiabic giil. A flbroUB-packad pump piaton li Dot i 
tlure wiU be danger of clog^ug the buroeia with ahreda of 



Fki. 21. Fm. 22. 

Kinney rotatinK plunger typn H.P. pump for fuel oil nor\ ico. 

Elnaey Sotetlni Plunger Pumps, now in use in the Naval Sen-ice 
for supplying fuel oil to the burners at a at«ady pressare are shown in Figs. ^1 
and 22. and dmcrib^ by Mr. E. B. Neal as follows: 

" The Kinney RotutinK PlimRor Pump consiata of a cylinder oiuting, having 
suction and discharge openiags to the pump rhamber The rhiimbcr is 
divided by a centre plate into tiro sections for the dual atvwnibly of the pump 
working parts. The cylinder casting la accurately marhioed at both ends 
and the heads are attached to it by studs and nuts. The heads and cylinder 
casting are toogued and grooved, requiring simply a light coat of ahellao to 
prevent leakage. Mo ya^Bti w* raqutrad. 



FUBL OIL EQUIPMENT 



305 



"The cylinder easting is provided with openings for flanged or screwed 
fittings for suction and discharge connections, according to the sise of the 
pump. The removable cylinder heads are provided with properly packed 
bearings for the pump drive shaft. The bearings are provided with adjusting 
nuts. The drive shaft may be extended or adapted to receive any desired 
type of power transmission. 

** The drive shaft passes through and actuates the piston cams to which they 
are keyed. The cams actuate the rotating pistons. The pistons rotate 
eccentrically, passing through the movable slide pins which open and cloee 
the discharge port of the rotating piston slides. All parts of the pump, 
except the drive shaft, are arranged in duplex opposed at an angle of 180 deg. 
giving perfect balance to the pump and no pulsation to the fluid. 

** In operation, the rotation of the piston produoes a high vacuum causing the liquid 
to flow through the suction port and follow the piston untU the oylinder4s completely 
filled. The port in the piston slide is then mechanically closed, remaining so until the 
earn has oompleted its full revolution. When the piston passes the suction port, it 
mechanically opens the diseharge port and immediately b^na forcing out the liquid 
in the cylinder chamber, at the same time drawing in a new supply. The ports are not 
in any way congested by valves or springs. 

*' Lubricating holes are drilled from the bottom of the piston slides through the pistons 
carrying the liquid which is being pumped to the cams uhder preesure, the parts thereby 
leeeiviBg perfeet lubrication. The abseaoe of meehanioai contact between the pistons 
and the cylinder insures a minimum amount of w«ir^n the cylinder and pistons. 

** The prominent features of the Kinney Pump are its positive action, extreme 
■impfieity, accurate and'substantial construction resulting in high mechanical e£5ciency 
and long service. The pump requires little expenditure for repairs or maintenance. 

The Kinney Pump may be connected to any typo of power transmission; belt, 
chain or gear. It may be directly coupled to engine or motor of correct speed for the 
pomp. The pump may be driven by pcnrtable or stationary steam engine, steam turbine, 
all types of electrie motors, also oil or gasoline engines. 

The capacities of the standard sises in which this pump is Manufactured are shown 
rn Table 2. 

T»bie S. Kinney Rotating Plnnfer Pumps for AM Lbs. Pressure 



%ae of Pump 



Theo. 



fi 



Is. per 
P.M. 



100 



Maximum R.P.M. 



Approximate Actual 

Gals. Delivery at 250 

lbs. at Max. R.P.M. 



High'«pead pumps 






4XIHXW 


1.8 


1000 


9 


4XIMXM 


2.25 


1000 


12 


4X2XM 


2.6 ^ 


1000 


18 


5X2XH 


3.2 


1000 


25 


6X2^XM 


5.00 


1000 


40 


6X2HX^ 


7.08 


1000 


60 


8X3XH 


11.25 


1000 


90 


8X3XH 


15.00 


1000 


120 



Low-speed pumps 





5X3XH 


9.3 


500 


30 






6X4XH 


15.0 


500 


60 






8X4X^ 


30.0 


450 


105 






9X4XH 


40.0 


450 


140 






10X5X1 


60.0 


400 


190 






12X6X1 H 


130.0 


350 


360 






I4X7XIW 


198.0 


350 


560 




1 


16X8X2 


325.0 


300 


800 




I 


20XIOX2H 


630.0 


275 


1400 




f 


25X13X3 


1225.0 


250 


2500 




It 


20 












Fio. 23. — Quioby screw type H.P. oil service pump. 



V^ Qulsby fcrew pump whiah hu rewotly beeD tested and approved 
lor use in the N&vy as a fuel oil service pump, ia illuatrated in Figa. 23, 24 and 
25 and is described by Mt. Wm. fi. Quioby 
u follows : 

"Fig. 23 shows s general arraDgenient, 
complete with turbine: Fig. 24 represents 
a cross-section of the pump through one 
set of screws; Fig. 25 shows a pair of shafts 
with the screws and gears in mesh as they 
are in the pump. 

"The four screws that act as pistons in 
propelling the liquid, are inount«d in patre 
on parallel shafts, and are so arranged t^t 
in each pair the thread of the screw pro- 
jects to the bottom of the space between 
the threads of the opposite screw. The 
screw threads have flat faoes and peculiarly 
undercut sides. The screws fit in the 
cylinder aa shown in the cross-section. Fig. 
24, and space enough is left between the 
screws and the cylinder and alao between 

the laoes of the intermeehing thi«ada, Fia. 24. — Quinby pUQp, croM 
to allow a close running fit without actual section. 




Fia, 25.— Quinby pump, detail of Intermeshtng underout threada. 



rVSL OIL SQVIPUKNT 307 

puiBM dirou^ thfa dumibw iotb* twoamfa of the cylinder iuidisfon»d from 
tha two ead* toward the eantrs by tbe kotlm of the two pitin of Krewa. The 
intermeehiDB portion of tha opposiM Mr»w in euh pair loaks the liquid in 
betweea the threade; eonaequently eaeh rarolution delivera posltivBly tbe 
oontenta of the spaoe between one eonvcdution of each of the threada leaa 
only tbe imall amount ot loes due tg Ibe dearanro between tbe aorewB and 
between the screws and the oylinder. The diaohVBe is in the middle of tbe 
. top of tbe cylinder. The power to drive the pump is applied to one ahafl 
and the teoond shaft is driven by means of a pair of Bears shown at "B," 
fig. 26. The jieceasary power may be applied by meana of a belt and pulley 
or by means of a direot-coiuieat«d motor or eDcine. 

" The puDip bM DO Internal paekbis. no mlTa and do Bmall morinc puts. There 
u DO end thrust or wear lb tha beariaxi dq* to tha beak pn^rure of the diflchHraB. b«caiiaB 
th« back preenre ii detiversd to tbe middle of thfr flylinder, and the endwise preseare 

opposite djreotim. Tha only opflniag frem the pressure chautber i> iDto the dLuharfe 
pipe and tbe only paeldof is in tbe stuffing boies where tbe two ahiilts pass tbroufh the 
cjlinder heads. 

" Tbeae pumps have been btnlt to pvs a steady prasure of from I to 500 Ibe, per aq, 

pnaaure, do sir baaka are required on oil preaaure llDes. 



Carfrtsai^ Air. 






r^ 



0^tidiKiim.af 6aig.iy»tr 

IfioffOiiisA ^ / 




Fio. 36. — Arranxement of oil piping on boiler front. 

I FiMl OU BMktwn. The object of heating fuel oil, and its effect on 
' TJaconty, is disousaad under at«miaatiou, page 2S0. HBal«n Bfe provided 
for tbia purpose. For the very light, Usa viaeous oila, heaters areof relatively 
little importancs, but with the heavier very viaeoua grades ol oil fuel, tbqr 
»B*uiiu) a positioD of importance in tbe design of the oomplete equipment. 
In arery ioilAllatioci, golUdant baaitaT uvmolty ■htnild be proridMl 

to bftndl* Im»*T Olla »t tuU pOW«r. Tbe most visrouB oils will requii« 
heating in some oases to above 240 deg. F. At the same time they are very 
^Dggiali to beat. This c^>aoity will be greatly ia eicess of that required for 
tbe light oil* at high power and for either tbe heavy ur light when cniisiDg 
•t reduced powers. If mm Urga tMktMria used, it will be found very difficult 
to regulate the temperaturee at capacities much below the designed maximum. 



SOS orL FUEL auRKim 

For thu raMon it u desirable to provide MT*ral saulltr haaUn ooruMotMl 
ID pajnlle) or to provide aome other ooDveiueDt method of readily incnuiag 
or decraaoing the amount o[ beatinK aurfaoe iitiliird. so that tbe portion in 
use can be operated at or luar ita tntuiiDuni ~ 

capadty. A Benaitive control ol the supply 
of Bt«aiD to the beatera would complete an 
ideal BiTBnsement for aiceamttly oootroUing 
the oil temperature. 

Ab the oil pasaea through the heater. 
Borne means of thoroushly ""'""g it by 
obatruotions. such aa baffling should be 
provided. Otherwise the oil will not be 
uniformly heated aa it paaaes to the 

When no iteUB is avsiUble and (he w1 in 



It 



heater vrill be necHuty to h»t the cul pn- 
panUiry to lifhtinc up. At the Mme time aome 

meaoa Should be provided tot droning the cold k 

iliUEKish nl out of tbe ptHmreoil linei between m, 

the hemtar and the burnen. Thli ean beat be ^ 
aocomptubed by fitting a unnll ^in. drain line 

from the dead end of the lupply line amiiea the ^ 

front of easb bnler and levlinc to the mietion _ 

oC Ibe KTvioe pump. It tbi> a not provided, it S 

will be necHWary to drun Ibi> oU oB into bucket*. - 

Fic. 26 illustTBteg  very (ood amncement for pj 
providing  drain for both the (^ line in licht- _ i^ 
inc ui> and the air bank when recharging with £ '^ 

•-■"—'" i 9 

TypM of H«Atan. There are a number 
ot types of fuel oil heatera manutaotuied. 
The three types illuetrated which are used 

extensively for marine instalUtioaH cover^ JjS 

the geoeral principles of design of prai>>J j;^ . 

tically all types. S S 

The Crunp fuel oil liM>t«r, manu-| "' 

factured W The Wm. Cramp 4 So™ SMp| 
it Emjine BuHding Co., is Uluatrated in* 
Fig. 27. This is a horiiootal heater with 
U tubal which are rolled and expanded 
into a header. The oil enters the bottom 
chamber of the removable head. Thia 

chamber is separated by a divisioD plate I: - 

from the top chamber or ouUot side ot the^ l 

heater. The tubes are seamless drawn .| I 

flt«el. tested to 600 lb«. Bteam for heating! 

enters the top of tbe outer shell and sur** , 

rounds the out^de of the tubefl. At the I 

bottom and connected to the st«an spaoa | 

is a drain for oBirying off the condensate. 

Thia drain leads to a steam trap wbjeh discbarttea either to the filter 
tanks or to an inspection tank. Frequently on the heater or on the | 
trap, or both, is locat«d a water glass which wiirshow oil on the Ufp of tbe 
water in the ilaaa, in case the heater leaks. 



FUBL OIL SQUIPMBNT 



309 



¥!«. 28 ahowB the lehatto ft Ko«rtiiic Co.'s "Z" Type OH Heater. It 
18 a ■traiirbt tube heater, steam passing through the tubes and oil passing 
anmnd the outside of the tubes, a full heating effect being obtained by means 
of baffles. The tubes are seamless drawn steel, expanded into steel tube 
plates. A special arrangement is provided which permits of free expansion 
and contraction of the tube bundle. The whole tube bundle can be easily 
removed for cleaning. 

Fig. 29 illustrates the BelUy MulticoU Tual Oil Heater. The steam 
flows through the ipirsl Beamlesi steel tube ooils. The oil passes around 
the coils. 

Most of the shipbuilding companies that install oil-burning apparatus 
make oil« heaters. 

Heating ooUs in storage tanks and bunkers are necessary to penmt of the oil 
being pumped to the main heaters, where its viscosity is reduced sufficiently for 
atomising; see effect of heating oil, p. 286 The tank heaters consist usually 
of coils of iron pipe about IH in. diameter located near or around the pump 
suction. These coils must have sufficient capacity to heat the oil, as it enters 
the suction, sufficiently to reduce the viscosity to about 375 deg. Engler, or 
lower. 

In the case of fuel tanks or bunkers, it would not seem necessary to 
heat the oil throughout the entire tank, and thus in the case of the double 
bottom, attempt "to warm up the whole ocean," provided local heating 
in the immediate vicinity of the pump suction can be carried out rapidly 

DESCRIPTION OP FIO. 17. 
NOMENCLATURE 



Mark 



Part 



Material 



II 
1 

2 

4 
5 
6 
7 
8 
9 

10 
11 

12 

13 
16 
17 
19 
20 
21 
22 
23 
24 
25 



Set of Gage Cocks.: Comp. "M" 

T..K-* flk^* / Wrought Steel 

Tube Sheet \ Claaa "C" Boiler Plate 

Flange 

Baffle Plate 

Baffle Plate 

Stiffening Plate 

Pad 

Pads 

Shell 



Retazders 
Retarders 



Studs. 



Forged Steel 

Wrought Steel 
Class "C" 
Boiler Plate 

Wrought Steel 
' SeamJeaa Drawn 
Wrought Steel 
Class "C" 
Shape 

««4" X Ha" Thick 
(Wrought Steel 
Class '*B" 



Nuts Wrought Iron 

Studs and Nuta \ ' ' '^^--^^ ^ " 

Bohs and Nuta / 
Pipes ^ 



NippU 

Tees 

|£U 

Ell 

Union 

Orommetl 

Tubes / 

Test Pressure (Water) 



/Class 'B' 
I Bolt Material 



Extra Heavy Brass 



[Copi)er 

\ Seamless Drawn 

i Steel Tubing 
/ Sheel 400 Lbs. Per Sq. In. 
\ Head and Tubes 600 Lbs. Per Sq. In. 



^ 



310 



OIL FUEL BURNING 



and unifon&ly enough to heat the oil as it is pumped &way. In this case the 
sixe and heating surface in the heating coil should be proportioned to the rate 
at which the oil is pumped out of the tank rather than to the eise of the tank. 

The situation relative to cargo tanks 
is different, owing to the high rate of 
speed at which the oil is handled by the 
cargo pumps. Prevailing opinion seems 
to be opposed to carrying very viscous 
oil in the double bottoms, on account of 
the very large heaters necessary; and the 
usual practice is in favor of heating the 
oil throughout the entire tank previous to 
starting the pumps. Thus, in the cargo 



NOMENCLATURE FOR FIG. 28 




Mark 


Part 


Material 


A 


Shell 


Cast Steel 

CI. "B" Annealed 


B 


Cover 


CI. "B" Annealed 


C 


Header 


CI. "B" Annealed 


D 


Tubes 


H'' 0. D. Seamless Steel 


£ 


Baffles 


Steel Plate No. 10-14 B. W.G. 



tanks of oil-carrying vessels, flat coils arc 
often installed near the bottom of the 
tanks in addition to the coils around 
the suction, the combined heating surface 
of the two sets of coils being figured at 
the rate of 0.10 of a square foot of heating 
surface per barrel of oil of the total 
capacity of the tank. About 40 per cent 
of this surface is allotted to the suction 
coils and 60 i>er cent to the flat coils. 

Strainerg. Thorough straining of 
the oil before it reaches the pressure 
atomiser is essential, otherwise the 
small orifice and the tangential passages 
become clogged, thereby destroying the 
uniformity of atomization and reducing 
the capacity. Also the fine gritty sediment 
causes considerable wear of the orifices. 

Basket type strainers are generally 
fitted on the suction lines. The mesh 
of the wire gauze used should be coarse; 
no finer than 28 mesh is recommended, 
as the primary object of the suction 
strainer is to protect the oil pump. Too 
fine a mesh is objectionable as it resists 
the flow of the relatively cool oil, causing 
excessive work on the part of the pumps 
and frequently resulting in lost suction. 




OilAk^ 



Dratn 



Fig. 28. — Schutte and Koerting 
"Z" oU heater. 



FVEL OIL EQUIPMENT 



311 



Daplax hlKh praHW^ baakat b^p* lU^lnsn are installed on the 
I pnaaiire mde of the service pumpe. generally between the pump and the oil 
I heater, but in some casesonthedischarge from the heater. The latter sirapge- 
it ha> a serioui objection when the more viscous oils are used, due to 
I the high lemperature to which the oil is neceBsarily heated, la the merohant 






Fw. 


30,— Reilly multicoil H.P. fuel oil heater. 




Hark 


P«t 


M.teriJ 




f 

N 

P 


Manifold 
Union Nut 


a«s"B'' Boiler Plate 

Comp. "Q" 
CoTop. "G" 
l"0. D. SeamleeeSleel Tubing 

1" O. D. BeamteaB Steel Tubing 
Comp. "Q" 





■ervjce, where heavy oils are freiiuently heated above the flash point, there 
n>uld bo a real danger when it becomes necessary to cut out and open 
ip a IieBt«r for cleaning. But there is also an advantage in locating the 
b-aiaer on the dixcharge side of the heater. The heated oil is very fluid 
od gives up the contained foreign subetanceB more easily, also a much 



OIL FUEL BURNING 




o = 

^ @ iu I I m o @ U 




Fio. 30,— Schutle and Koertins H.P. Duplex t\uA oil 



FVSL OIL EQUIPMENT 



313 



..-5&tf 




Shtds mustnal- ^nttnrh 
0//^paces. 



/ 



Care to be taken in Construction 
'''thaf' Handle of Basket Presses 



y Firmly on Lo^. 




GasTap for Drain _ 

^ Section D-D 



Strai n9rt 

Area through Basket 44S2SqJn 

Area through mreMtsh ISM ".* 

ATeaofZmHoTTle 3.l4l65ql/t 

Rath is/foJ. 



NOMENCLATURE 



Mark 


DeBcriptloQ 


Material 


I 


Body 




II 


Cover 




III 


Basket 




IV 


Plug • 


• 


V 


Gland 




VI 


Ring 




VII 


Nat 




I 


Pin 


Comp. "G" 


3 
3 


Packiiw Ring 
Plp« Plug 


Vulca Beaton 
Comp. •' Mn-R" 


4 


Jaek Screivs 


Steel Class B Bolt Material 


5 


Studs 


Hteel Class B Bolt Material 


6 


Nuts 


Wrought Iron 
Steel Class "C" 




Handle 




Wire Mesh 


Steel 




Ko. 30 ws., 0.014'' Dia. Wire 


• 



rest Pressure 600 Lbs. 

SsBSidle. Brsss Strips, Screws in Basket Tinned. 

FiQ. 31. — Cramp's H.P. Duplex fuel oil strainer. 



314 . OIL FUEL BURXINO 

finer mesh gause may be used. In the Naval service, brass wire gauze of 
42 mesh to the inch is generally used for pressure strainers. 

In addition to the above, many makes of presBure atomisers are eqtdpped with 
individual strainers. If proper attention ia devoted to the care and deanlineaa of 
the large pressure strainers on the main supply line, atrainers for individual atomisert 
are an unnecessary and expensive refinement. 

Duplex strainers should be of sufficient capaeity that one may be cut out for cleanini> 
while operating under full power, so constructed as to be readily opened and cleaned 
and so designed that the flow of the oil shall bo from the outside into the centre o 
the basket, in order that dirt and sediment will be depoeited on the outside surface o 
the basket. 

Figs. 30 and 31 illustrate two duplex pressure strainers that are extensively 
used in marine installations. The one shown in Pig. 30 is manufactured 
by the Sch^die & Koerting Co. The one shown in Fig. 31 is manufactured by 
The Wm. Cramp & Sons Ship <fc Engine Building Co, 

Oil Piping. In the Naval ••rvlce, specifications require that the 
pressure serrice piping be seamless drawn steel tubing with ''expanded 
on" steel flanges. Flanged joints are ground and are required to be oil tight 
under test without the use of gaskets; test pressure. 600 lbs. Suction piping 
is steel, lap-welded, and expanded into flanges. Thin, tough, fibrous paper 
gaskets are allowed; test pressure", 50 lbs. Oil piping should be exposed as 
much as possible to insure prompt detection of leaks. 

For merchant senrice, extra-heavy welded-iron or steel pipe, with screwed 
joints and with extra-heavy galvanized-iron fittings, is used. Flanges 
are screwed on the pipe and mamla paper, card board or special oil-proof 
packing may be used for gaskets. Rubber is not allowable on account of 
sulphur in the oil. Copper piping is not used on account of the sulphur, 
but brass and composition fittings, valves, unions, etc., may be safely used. 

The suction piping should be large. The Newport News Rule limitf 
the designed velocity of Mexican oil through suction pipes to not over 20 ft 
per minute, the oil being heated to reduce the viscosity to about 300 de^ 
Engler. For discharge pipe lines they consider 100 ft. per minute allow 
able in small pipes, the viscosity being reduced to 15 deg. Engler or under 

Mr. C. F. Bailey of Newport News Shipbuilding and D. D. Co. states that **Ai 
we pipe from the service pumps to the oil burners we reduce the speed of the flow nea 
the end of the Unes, i.e., we do not reduce the piping in proportion to the oil used, as w< 
find it necessary to reduce the flow in order to maintain the pressure at the bumera oi 
the end of the line farthest from the service pumps. With Navy fuel oil, and where w 
do not make allowance for changing to heavy oil like Mexican oil, wo allow about doubl 
the speed in the discharge pipe to the burners that is allowed with Mexican oil. Fc 
instance, in the U. 8. S. Pennsylvania, the service-pump discharge to the heaters is pre 
portioned for about 130 feet velocity per minute, the discharge from heaters to burnet 
is proportioned for about 230 feet per minute in 2>^-in. and 2-in. pipes, reapectivel} 
As the lines reduce we have'in 1 H-in. pipe, 185 feet ; in 1 >4-in. pipe, 105 feet; and in fi-it 
pipe, to each burner, 128 feet; velocities per minute. Our Destroyer practice in regaA 
to piping and oil speeds is substantially the same as that for the U. S. S. Pennsyhaniaf 

Valves. *For valves on suction lines designed for viscous oils, the gat 
valve is preferable, on account of reduced friction. On delivery Ux&ea 
globe valves of a regrinding type give satisfaction. There is no occasioi 
to use needle valves. Where fine regulation is required, as in some case 
with steam atomisers, there are several types of valves which open gradually 
on slotted or V-shaped passages which give better and more conaisten 
results than the needle type. All valves for high-pressure work should b4 
extra heavy with bonnets screwed over, not into, the valve body. Speciall] 
designed and packed plug cocks may be used in small sizes for quick action, 



BOILER ROOM ISSTRUMBKTS 315 



IndiTidual atomiien are Irequently coDDeetod to the oii aupply line by J^ 
or ^-in. Beiible piping. Extm heitvy aonealod cupjier pipe ia usad Cor thii 
purpoee but there la now oa ttie market bq eioelleDt and very flexible oil 
tiglit braided lubiog, known as '*RiQai," that is superior to the copper pip* 

Air Cuahlon CtMuabon. Fig.aeshows 
oil supply W>^ aeroas front ol boiler, draia 
lines sod air banki tu fitted with reriprocat- F 
ing Fuel oil servioe pumpa. It la a matter 
of opinion as to whether aiiohambeistihoiild 
be fitted at the discharge of the aerviee 
pumpa, on Uis supply line iuat before the 
oil reaches the atomidtars or at the dead end 
of the supply line. In any oaae the flow 
oil should be diroot into Lhe cuahionins 
Ghamber and if a valve is fitted to cut out 
the chamber it should be a w^te valve. 
BOIUB ROOH DISTRUimrTS 

Tb« draft k»uV«i oommnnly known as i 
IDUlonM^ttfTf is ufied to measure the pres> 
•Ure in tbc tire room above the atmospheiw 
and also pressure differencefl in different 
partaof the boiler. It provides an exceHent 
means of meaauiiiw dr&ft ii 
with the study ol furnace efficiency and 
boiler design. 

Benides csrryinR off the w 
combustion, the smoke pipe r:reat«fl  draft 
*r difference in premntrc which, at natural 
draft, is the means dependnd on to draw the 
«fr for combustion into the furnare. This 
draft is dependent on the diflereni 
weight between the ctriumn of hot s 
the amoke pipe and the weight of an equal 
ecdumn of relatively cold outside air. 
•eale ia crsduated to rernrd t) 




Pra. 32. 



« lb. p 



ir droit ii 



1 inch— O.aJO ounc 



.tOBMit 



m the t«o 



Ml 



i U tube. The pteaaure 



I, In. 




Flo. 34. 



board el 

EB careful leveling. 

Oil Tharmomaten uhould be installed in the following locations: on 
the pressure oil supply line to each boiler, to record the temperature of the 
ml just before it reaches the atomisers (see Fig, 26) ; on the discharge from 
the oil beater, and. on the suction from each storage tank. In addition, 
* ttwrmometer ia frequently placed on tbe oil servioe pump disaharge to the 
ml fuel heater. 



316 



OIL FUEL BURNING 



Oil Pressure Qauges should be provided on oil supply lines at each 
boiler near the atomizers, and on the diaoharge from each pump. 

Smoke Pipe and Furnace Temperature. In the study of bofler and 
furnace efficiency and in the computation of heat balances it is essential 
that the smoke pipe or uptake temperature of the waste gases be known, 
and it is desirable to know furnace temperature. Nitrogen filled mercurial 
thermometers graduated to 1000 deg. F. or base metal thermocouples 
are very satisfactory for smoke pipe temperature observations. The re- 
cording type thermoelectric pyrometer is frequently preferred as giving 
a continuous record. 

For observations of furnace temperature the Optical pyrometer is perhaps 
the best. The use of precious metal thermocouples is expensive on 
account of frequent renewals and is generally unsatisfactory as the tempera- 
tures of oil-fired boilers is close to the maximum range, and quite often is 
above the melting temperature of platinum. Of the many thermocouples, 
the potentiometer type is known to give excellent service. 

Potentiometer Type of Pyrometer. When two diseimilar metals are 
joined, forming a completed circuit, due to their difference in jtotential 
and the difference in temperature of the two junctions an E.M.F. appears 
and there is developed a flow of current. The resultant net or effective 
E.M.F. will be proportional to the difference in temperature of the two 
junctions. Such a device is known as a thermocouple. 

In the ordinary electrical pyrometer a galvanometer or millivoltmetor, 
inserted in the circuit, measures the current flowing. The deflection 
of the millivoltmeter, however, is dependent not only upon the electromotive 
force generated but also upon the resistance of the circuit and upon the adjust- 
ment and condition of the instrument. 

In a p3nrometer of the potentiometer type the E.M.F. developed by the 
thermocouple is balanced against a known E.M.F. and the reading is 
obtained when this balance is exact, that is, when no current flows. Under 
these conditions it does not matter what changes may take place in the re- 
sistance, length or size of the leads, or of the thermocouple. 





Fio. 35 



Fro. 36. 



Fig. 35 showB a wiring diagram of the potentiometer. The thermooouple is at U, 
with its polarity as shown. It is connected to the main circuit of the potentiometer 
at the fixed point D and at the point O. 

A current from the dry cell Ba is constantly flowing through the main, or eo-calied 
potentiometer circuit, ABCDQBF. The section DOB of this circuit is a slide wire of 
uniform resistance throughout. The scale is fixed on this slide wire. The current from 
Ba as it flows through DOB undergoes a fall in potential, setting up a difference in 
voltage, or an E.M.F. between D and S, and lUso between D and all other points on 
the slide wire. The polarity of the former E.M.F. is in oppoutioA to the polarity of 



BOILER ROOU INSTRUMENTS 



317 



a iBto iha poteirtionietBr kt D and G. By ■iin>lD< 
t iHlta win k point !■ foood wh«e th* vclUce tHtman D and <7 is the slida 
win u iott equal to tbe ToHaca between t> «ad O ■• (CBented by the tlucmanaupl*. 
A [KtvaDDraeter iv the ttHrmODQtiplF elnnilt ladioHteH whan the balaaoe poiDt u reached^ 
■inoe At tfai> pirint the gAlvuiaaietar oaedle will Btaod motleEileiH whan ita circuit ii apaued 
abd dosed. 

9 wiH vary with the cnin«ii flowinc thiou(li it fiom the 
' ia ahcnld ba prm-idBd. By intfoduciDd a aCandanl 
1 Ks. 36 tbla ain be effeMcd. The sell  eomwirted at C and fi to tha 
poCentknneter ^reuit wbcaevwr tlu pfrt^atioEBetfv aorraot u to b« atAitdArdiiaiL At 
ttu time the tatranoiDetw ia ^taeei in eerioa with S. C. The vuiable iheoatat R w 
then adjiiated uatil the ciirreTit floving Lg nuch that ae it flow* thiouch the (taadanl 

o( IhestaDdard sell 9. C. At iMa time thsgalvaDoinBteT will iodieate a balanaa in tba 

V DCS lua bKQ itaadardiud . 




vWv\AA 



Fiu. 37. 

TbA Optical fjtazmAMr. For meaauriag temperatures from n dull led 
(about 1100 deg. F.) to the highest Imown temperature, an optiml pyrometer 
mine ^ bitlanee nMthod of comparmg luminoui rKdiation. is the mostaocurBte. 
The gr«atmt auoonse haa been obtained hy separating out one color, usually 
red. {rom all the light emitted by an inoandeeiioat body and comparing the 

mnty of this one oolOTed light nltfa the int«nBity of the llchC of the »ame 
oolor from a Btandard Hmrae of light. The eye is very Hemitiva in jndging 
«Uah is the l>Tighter o( two araas, espeeially when obs area is small and auper- 
impoaed upon the other. The brighRiees of the two area* rauie them to be 

do equal by varying the intensity of the standard of compariaon. 
The principle of an eneDent type of optical pyTomcter is llluitrsted in Fi«. S7. 
£ ifl A lens tfartm^ whi^ rwUatioiu from the incandp«aent body nre brousht to a locua at 
tl^ {wtnt /, In the poaition of the iniajre produced by thcr leu ia placed a tuSKSten 

taiued in a portAbte case which alio contains a rheoetat and an accurate mLUiamDietff. 
Tbc incandeaoent filament and the image prodaned by the lem'is absecved through the 



318 OIL FUEL BVRNJNO 

whereupon the fituneat Uendi or beeoBMS indietiagawhAbte in the bnoksround formed 
by the iraac^ of the heated object. When a balnnee has been attained, the obeerver 
notee the reading of the milliammeter. The temperature eorreeponding to the current 
ie thue read from a calibration curve supplied with the instrument. 

As the intensity of the fight emitted at the higher temperatures becomes dassling 
it is found desirable to introduce a piece of red glass in the eyepiece at R, This also 
eliminates any question of matching colors or the observer's aUlity to distinguish colors. 
It is of further value in dealing with bodies which do not radiate light of the same com- 
position as that emitted by a black body, since the intensity of radiation of any one 
color from such bodies increases progresnvely in a definite manner as the temperature 
rises. The intensity of this one color can ther e for e be used as a measure oi temperature 
for the body in question. 

The praeticAl advantagee of the instrument are: (l)It is light and portaUe; (2) 
large surface of sight is not required; (3) distance of the observer from the hot object 
is not important; (4) adjustment is rapid; setting is precise; and (5) intensity, not color, 
of light is matched. 

Smoke Chmrt. In order to have a uniform aystem of determining and 
reoording the density of smoke produced, the smoke chart, otherwise known 
as Bingelmann's Scale, is used. There are six cards, numbered from to 5; 
the first is entirely white, Nos. 1 to 4 are ruled into small squares by lines 
of varying thickness, and No. 5 is entirely black. The ruled cards have 17 
horisontal and 10 vertical lines, spaced 10 mm. apart between centres. For 
card No. 1 the lines are 1 mm. in width; for No. 2, 2.3 mm.; for No. 3, 
3.7 mm. ; and for No: 4, 6.5 mm. No. represents no smoke. Nos. 1 to 4 
represent 20, 40, 60 and 80 per cent smoke respectively, and No. 5 repre- 
sents 100 i>er cent smoke. 

These cards are hung in a horisontal row about 60 feet or more from the observer and 
in line with the smoke pipe. At this distance the lines on the ruled cards are not visible 
and the cards appear to be of different shades of gray. The observer glances from the 
cards to the smoke and decides whioh one is nearest in shade to that of the smoke. 
Observations should be made and recorded in terms of percentage of smoke and the 
average taken as the average density of the smoke for the test. 

Flue Gas Analyiit is essential to the accurate determination of the gases 
of combustion in connection with apportioning of the heat losses. An intel- 
ligent use of the gas analysis instrument is the most valuable aid in obtaining 
the maximum furnace efficiency. It is a positive gauge on the unount 
of ezceei air and is probably of much more assistance when oil is burned than 
it is when coal is used as fuel. This instrument and its use is discussed on 
page 482. 

Oil Meters should not be considered as replacing tank soundings, but they 
are of great assistance to the engineer in procuring hourly records of oil 
consumption in connitction with computing curves of' consumption of oil 
under various operating conditions. With proper precautions, they serve as 
an excellent check on the tank soundings. If means are provided for dr- 
culating the oil through the system prior to lighting up, care should always 
be taken to by-pass the meter, or Uie oheok on daily consumption will be 
destroyed. 

Meters that are accurate within 1 per cent through a large range of capacity 
and pressures are now being manufactured. Two repretentatlTe types 
that have given satisfactory service are the Empire Oil Meter and the Bowser 
Oil Meter, described hereafter. 

The Kmpire Oil Meter is a positive displacement meter of the oscillating 
piston type, and consists of a measuring chamber enclosed in a case, and 
provided with the necessary gear train for transmitting the motion of the 
piston to the registering mechanism. 



BOILSK nOOit INaTRUMBNTS 



319 



TtM BOMtmiriiii etaftmbv of the Empire Oil Met«r oonBiata of an uinular 
ebamber, formed b; an outside riag and two heads. On these heads circular 
projections form the inner wall of the annular chamber, a space being left 
between theee proiections' to allow for the workins of the web of the piston. 

The neceBHiuy outlet and inlet ports are eJbo formed in the heads of the 
meASurinc ohamber, A bridse ia placed in the annular abamber sepantting 
the inlet and outlet ports. 

The platon ia a eylindiiesl ring provided with a web which works with an 
osciUaliDB motion around the central abutment of the meaiuiing chamber 
and is provided with a projection on its center which acts as a guide for the 
piston and keeps it in joint. toimiDg oontact with both the irndda and outaide 
walla of the annular meaauring chamber. 




Fio. 40. 



Fia. 41. 



Tbc aecompsnyi 

The cue chamb 
ease chsmbei. and tht 



diicruu, Fiis. 38. 39. 
ml ma action of the meuuiinc chi 
chamber A is of eyliadricai form 



40i 41, and 42, and the duociption, 

and has an Bbulment B central witi 
C makca a divigloa between Ulb abut 
th aide of tbia abutment are porta D and B; D ia tha iulel 
and g tbc outlet port. 

Tbe piaton ^ ia a aplit rina of oylindrieal form hanng a slot which phb» over th< 
diai)hTB(in C. Tbia iriiton baa a motion around the ciae in which the centre ol the pialoi 
JM Bribes a idrela around the esntra of the saae gbambet. but as the pialon do«e no 
ittellTalate.biitilidisbBckaiidlartliupoothI«dataj ~ ~ 






820 OIL FUBL BVKNIfiO 

baenc^ledui "oMdllfttinc nwtir," to dutincauh it ftou sifban in vhkb tb* platoQ aur 

rotite upon iu own uii. 

Referring to Fie. 38, the piiton ii showD u tiBvdins in tb« dincUon 

■Dd U "ft" Hilh the will oF the kbntment. The putoD i ' ' 

C. Thntlon. the piBtoD divides the sue oluinber int 

In vhich tbe vpnata 1 >nd 2 m formed ouMde af tbs piilon, tha al 

■ire fortned inuda of tho f^ton. 

Aathe piaton moveain thodiraotion iliowiiby thautoir in FiC' 38, in 

3, which coi)imunicftl« with the inlet port D are enlarcini their volumea while 4 
ajiAcea 2 and 4, nbioh communicate with the outlet port E, we reductog their v(rii 




Fio. 42.— Empire H.F. oil imter. 

At the poaition shown in Fi^. 39. inlet apace 1 continual to incieaie iU Tolume. Space 
4 becomee lero. Space 3, iniide the piston, haa reached ita maximum volume and haa 

4, ehui(» from an inlel to uQ outlet ipacc and openi conimunicBliDn with outlet port B. 

In Fie. 40). 

aothcr quarter cycle; space I. uliil in coDimuntca- 
'nlar^e; new inlet apwre 3 in enlarging; spacea 2 

When poaition Fig. 41 is mached, space 1 haji attained ita rnaiimum ^le and merging 
with ipace 2, becamn an outlet spare; it opena communication with outlet port B 
A new apam 1 beidns to lorm («en In Pig. 38). 

The praaure upon the piitou i> all in the line connected by Uie poinU of conUiit. 
a and b, and this ig al right angles to the motion of the platon. 

The oil meter as arranged for use in the U. S. Navy U provided with » 
(tf ai|[ht reading (x>UDl«r wfaioh i«ada in gaUooB and is driven by a pair of 



BOILER ROOM INSTRUMENTS 



321 



berol gears and a counter abaft, oalibrating gears being installed between the 
countershaft and the regbter shaft. 

The Empire Oil Meter has been made in a number of special sixes for heavy 
pressure service for the United States Navy. Among these sises being the 
following: 



Siscs, inches IH 2 


2H 


3 


3H 




^' I 




Csoaoitiea. sal. per min ; lto20 1 2to40 


2 to 50 


6 to 76 


6 to 100 


spw» . B» PC , 1 w [ w 





The Bowaar Fuel Oil Blater of the positive displacement type, for accu- 
rately measuring the quantity of liquid flowing through a pipe, is shown 
in Figs. 43 and 44. This device consists essentially of a rotating element 2 
eccentrically located in a body 1 . Mounted in the rotor are two sets of sliding 





Fig. 43. 



Fio. 44. 



Bowser H.P. fuel oil meter. 



blades 3, the edges of which are continuously in contact with the bore of 
the foody. This bore is formed by an are of minor radius a at the top and an 
ate of major radius h at the bottom, both struck from the centre upon which 
the rotor revolves. £ach arc forms approximately 90 deg. of the perimeter 
of the bore and they are connected by curves. The inlet and outlet openings 
are located opposite each other and are rectangular in shape, extending the 
full 90 deg. on each side of the bore formed by the curves. 

As the liquid enters the meter it fills the cavity formed by the difference between the 
minor and major radii of the bore, and due to the pressure exerted upon the unbalanced 
area of the blade the rotor is revolvecL In revolving, the blades, whieh are 90 deg. 
apart, form a poettiye seal between the inlet and outlet ports, thereby causing a definite, 
amount of liquid to be passed through the meter for every quarter revolution of the 
rotor. 

This motion is transmitted by means of the rotor shaft (4) through carefully cali- 
l»atcd gearing to the dials which read directly in gallons. This counter mechanism 
is mounted on the head of the body (either right or left), and is contained in caning 5. 

To reduce the power required to operate the meter to a minimum, special care is 
exereiaed in the design and machining of the bore in the body. The curves connecting 
the arcs are of the form known aS uniformly eoeelerated and deaccelerated motion which 
insarcs the least frietion of the sliding blades upon the bore and still maintains a positive 



TfaiB meter is built in nine sixes and three weights, to work under pressures 
up to and including 1000 pounds per sq. in. These meters are cdso designed 
to include a valve which can be set to allow a predetermined quantity of 
21 



322 



OIL FUEL BURNING 



Number of meter 


Oallona per 
minute 


A 

inches 


B 
inches 


C 
inches 


D 

inches 


17 - 
inches 





5 


6H 


4^ 


3H 


2 




1 


9 


10 


6H 


7H 


2We 


4M 




14 


10 


6?i 


7H 


3V<« ' 4f« 


3 30 


I2H 


9M 


7H 


4 


4H 


4 , 50 


MM 


9M 


m 


5 


4H 


5 ! 100 


19 


nn 


9^U 


yyi 


4fi 


6 200 


22H 


17 


lO^Me 


6H 


4H 


7 1 450 


25 


21 


12 


8H 


4H 


8 


900 


30 


25H 


15W 


mi 


4H 


9 1350 


34 


30 


18 


14 


4H 



Measuremont of Boiler Water or Steam is rarely accompliahed on 
board ships in service with any degree of accuracy. On trial trips, calibrated 
tanks are frequently installed on deck but these are removed upon the oom- 
pletion of the trials. In general, calibrated tanks and tanks on scales are 
too large and unhandy for permanent installation on board ship. 7eed. 
tank loundings serve to check the amount of water on hand and aid in 
keeping a record of the make up feed but they aoffrd no data of value in 
connection with boiler evaporative efficiency. A suitable instrumrat, for 
use on ship board, that will supply reasonably accurate data on the actual 
water evaporated into steam by the boilers would do more to save fuel than 
any other one instrument. This data in conjunction with fuel consumption 
would enable the engineer to set a standard of fire room efficiency. 

The venturi meter meets the above requirements, but it neceadtates the use of 
longer leads of straight pipe than are generally available on ship board. This objection 
also applies, in most cases, to the steam flow meters on the market. There is an 
additional objection to the majority of flow meteis, though giving excellent scirvice in 
stationary plants, where they can be accurately leveled, they are sensitive to motion 
on ship board. These meters are being rapidly devdoped and, it is believed, will soon 
be found in successful operation at sea. 

OPERATION 

Practical Requirements. The oil must be finely atomised just prior 
to coming in contact with the air for combustion. The requisite quantity 
of air must be intimately mixed with the oil and excess air reduced to a 
minimum. A high furnace temperature must be maintained, by the 
use of sufficient refractory surface, to assist in complete combustion. Com* 
bustion must be completed before the combustible gases come in contact 
with cooling surfaces and become chilled below the ignition temperature. 
Boiler heating suxf aces must be protected from locaUsed heating caused 
by a blow pipe aoUon; heating should be uniformly distributed. 



liquid to be discharged through the pipe when it will sutomatioaUy dose, 
and if desired, automatically stop the pump. 1 

For fuel oil and similar liquids Table 3 of capacitleB may be used to deter- 
mine the sise of meter to use. 

Table 3. 



OPERATION 323 

Prior to Ughtlng FItm. Ensure that the whole oU ijttam is dean and 
free from dnrt, waste, flakes of aheUac, red lead, etc. Inspect and clean all 
ftrainert, this ahonld be done frequently while underway; see that wire 
gause is in good condition and that the proper mesh is used. Thoroughly 
clean atomiiing tips, place and properly adjust same in air registers. 
Close individual atomizer throttle valves. Drain or pump overboard, 
water in oil tanks that has settled out. If oil is very cold and viscous, 
and pumps have difficulty in getting a suction, use heating coils provided in 
the tanks. If air chaxobers are provided, drain and charge with compressed 
air. 

Ensure that furnace and bilges are free from explosive ffMes. Pump 
out and steam out aU bilses; wipe up all oil on floor plates and elsewhere. 
It is excellent practice to do this at least once each watch while steaming. 
Blow out furnaee with air or steam, or, if neither are available, thoroughly 
VentUate. 

Start up pumps and put oil pressure on lines. Inspect for oil leaks. 
By-pass meter until ready to light up, otherwise it will operate wHle air is 
being pumped out of the line and while oil is being circulated. Warm the 
oil with the heater. See that torch is provided and ready. If light oil 
is being used, everything is in readiness for lighting fires as no trouble is 
experienced in atomizing oils above 23 deg. Baum6 at usual temperatures. 
When no steam is available, the hand oil pump is used until steam is generated. 

A suitable lighting torch may be made by securing a few loose turns of 
asbestos wicking on the end of a rigid wire rod about 2)^ to 3 feet in length. 

Dampen in uptakes or stacks are not generally installed In oil burning 
boilers, but if provided, they should be wide open before fires are lighted. 

lAghtAni Fires. Note that there is sufficient pressure on the oil and that 
it is at the proper temperatiire for good atomization. Make sure that the 
center atomizer has a small siser orifice. Light torch and place near and just 
under the atomizer. Stand clear as a precaution against blow backs. Have 
blowers warmed up and just ready to turn over if steam is available. Open 
atomiser throttle, and the oil will immediately light up and readily bum. 
Be sure to note that the oil is being properly atomized. A dirty atomiser 
will cause heavy black streaks. The presence of considerable water is in- 
dicated by sputtering that is easily detected. Srery precaution should 
be taken to present unbumed oil from coUectinir in the furnace as the 
hot briofc ffasiileB it and there is serious danger of a violent explosion. 
Proper pracautions and common sense eliminate such dangers. 

When extra burners are lighted it is preferable to use the torch each time 
while the furnace is still relatively cold. After steam is generated and the 
furnace is hot, additional burners may be safely lighted from adjacent 
burners in operation. No matter how hot the furnace may be, if all burners 
are temporarily secured, do not attempt to relight from the incandes- 
cent brick work. The most serious accidents have been occasioned by 
tlus practice. 

Always light the centre burner first, then adjacent ones on each side. 
Keep the number in operation arranged symmetrically around the centre. 
This gives a more uniform^ distribution of combustible gases in the furnace. 

It is ad'v'isable to avoid* raising steam too rapidly as the rapid change in 
temperature is hard on the refractory lining tending to spall and loosen the 
brick. With express type boilers, rapid raising of steam from a cold boiler 
is more injurious to the brick work than it is on the boiler. With Scotch 
boilers this condition is entirely different. 



824 OIL FUEL BURNING 

Unless a botl«r is to be cut out, at no time should the steam pressure be 
allowed to fall below 75 per oent of the authorised boiler working pressure. 
With a low staftin pretture th^ blowers cannot be speeded up to supply 
air for lightinf; the additional burners necessary to meet increased demand 
for steam without making smoke and causing vibration. 

Pressura on Oil. The oil pressure does not enter into the problem of 
burning different oils. The question is purely a matter of ascertaining 
the temperature requisite in the case of each grade of oil to obtain the proper 
viscosity. When this viscosity is maintained, the oil pressure may be the 
same with every grade of oil used. With atomisers properly designed and 
kept properly cleaned, oil pressures from 125 to 250 lbs. give practically, 
equally good atomization. I&eraasing the prouurv above 125 Ibe. merely 
increases the capacity which, other things being equal, is very nearly 
proportional to the square root oithe pressure, •'.«., to double the capacity 
will require four times the pressure. However it must be remembered 
that excessive oil pressures require a corresp>onding increase in air pressures. 

Difficulty in Lighting Fires. Trouble is to be expected with heavy oils in 
first lighting up. It will probably be necessary to install small charcoal oil 
heaters to be used, when no steam is available, for warming up heavy oil 
before lighting up. A further aid in lighting up under a dead boiler would be 
a half inch line tapped off the dead end of the oil line across the front of the 
boiler and led to an oil tank or to the service pump suction. Before lighting 
up, the valve on this line may be opened and the oil circulated through the 
system until hot oil from the heaters fills same up to the burners. This yiVI\ 
eliminate the necessity of drawing off the cold oil in buckets at the burners 
to obtain heated oil in lighting fires. 

Heavy Soot on Tubes. Heavy deposits of soot on tubes always accom- 
panies heavy smoking, no matter what kind of oil is used, and is a sign 
of incomplete combustion. This condition is exaggerated under natural 
draft and at low air pressures and may be due to several causes; insufificient 
air for combustion, poor atomisers, oil too viscous, atomizers improperly 
adjusted, poor design of installation, unstrained oil, etc. 

Heavy Smoke. Sm6ke is an index that something is wrong. When 
complete combustion is obtained smoke is eliminated. But it should be kept 
in mind that complete combustion in a boiler furnace does not necessarily 
mean maximum efficiency of the boiler. Complete combustion with a 
minimum of excess air does mean mail mum furnace and boiler 
efficiency. For this reason it is often stated that the best practical results 
arc obtained with a very light gray or brown smoke leaving the smoke pipe, 
because when the smoke pipes are smokeless it is difficult on board ship 
to determine the amount of excess air entering the furnace, and as this amount 
increases, the furnace efficiency falls off rapidly. A trace of light brown 
smoke emitted in a uniform manner from the smoke pipes generally indi^^atm 
about 10 to 15 per cent excess air. To remove all traces of smoke will, in 
most cases, require an excess of 50 i>er cent or above. 

If smoke is due to other causes than Insufficient air, these causes must be elimi- 
nated before the smoke can be used as &n indicator of the best practical furnace efficiency. 
For example, if one or two atomiiers are dirty, streaks of dense oil enter the furnace, 
and pass out the smoke pipe partially consumed, causing smoke even thoujch there may 
be a very high percentage of excess air. A trained eye can often tell the difference be- 
tween smoke from such eauses, and that due to lack of air, as it is generally iiregulat 
and streaked. 



OPERATION 326 

Caj'boii on atomjilng tips is the surest sign of their ixnproper 
location. If the atotnistr is shoved in too far, an eddy is formed in the 
entering air currents. A fine fog of oil is drawn back behind the face of the tip 
and is deposited on this face, on the side of the tip. and occasionally for some 
distance back on the burner pipe. This latter is an extreme case, where the 
atomiser has been shoved in several inches beyond the proper point. In 
extreme cases jets of ragged flame are also drawn back by this eddy, sometimes 
oompleteiy hiding the tip from view. 

Carbon on 7umac0 Opening!. If carbon forms on edges of the 
fomace openings, the atomizers have been drawn back in register too far, 
or as is often the case, the furnace opening is irregular due to patching up 
of the brick work, and edges of bri9k or mortar project into the outer film 
of the cone of oU. If earbon forms on atomlainc tip and also on furnace 
oponinfT and there are no mortar or brick projectionB, the opening has been 
reduced to such an extent that the btimer cannot be drawn back far enough 
to prevent the eddies in the air current described above. This is a fault 
of design and can be eliminated by increasing the furnace opening or 
by a new demgn o^ register. It can also be eliminated by using an atomizer 
that gives a smaller angle to the cone of oil, but this is not recommended 
uikiess there in sufficient depth to the furnace, to permit of complete combustion 
before any oil strikes the back wall. This is rarely the case In marine boilers. 

Sard carbon deposita on*tubes and on furnace sidea and bottom 

are due to the oil striking the tubes or the brick before it has had'time to burn. 
This is frequently experienced even with the light grades of oil, 'and is caus^ 
by two defects: one, design; the other, operation. Wing and bottom burners 
are sometiipes plaoed too fiear the tubes and the furnace bottom. As a result 
oil strikes these surfaces and is carbonized before it has time to form an in- 
timate mixture with the air and become completely consumed. Due to the 
necessity for cutting down the furnace volume in Naval boilers to a minimum 
this trouble is frequently met with. 

Under operation, the causes are the same as those that produce excessive 
soot and smoke; namely, the failure to obtain an intimate mixture of the 
entering air and the oil at the register; this is more often caused by the im- 
proper location of the atomizing tips than anything else. It is sometimes 
due to too much excess air entering around the cone of oil and thereby cooling 
the flame down so that combustion is not obtained until some distance in the 
furnace; this permits the particles of oil thrown off at the greater angles from 
the axis of the tip to strike thci furnace bottom, side walls or tubes near the 
front of the furnace before they are burned. This cools them below the 
combustion temperature. The lighter gases vaporize and bum; the carbon 
remaining adheres to the surfaces as a solid moss. The same occurs when 
there is insufficient air for complete combustion, but this need not be con- 
sidered, as the tendency on board-ship is toward too much excess air. 

The Botieeable increase in ihe amount of esrboii deposits when rimous oils of asphftltio 
base, stieh as Mexieanaad GaKforaia, are burned, is probahhr due to the large proportion 
of unaaturated'hydroeaitiotta contained. These are heavy and riow burning. Other 
tldogB being equal, they require a longer time in which to become eomplet«ly consumed. 
Therefore tiiey require a longer combustion paUi or some means must be resorted to that 
will hasten the combustion. This can be accomplished by increasing the velocity of the 
entering air for combustion. The area of the openings in the air controlling registers 
must be dosed a proportional amount so that the volume of air remains the same. It is 
frequently stated by engineers that "more air 10 needed to bum Mexican oils.'* This is 
not correct acid should be stated as follows: A greater air preerare Is required to 
bum Meilcaii oils, as an Insreaae in the air pressure is necessary toobtaiaaBlnereaBe 
in the entering vdodty. 



326 OIL FUEL BURNING 



PBXCAUTIONB IN BfANAaKMSNT 

While oil-burning boilers are subject to the same derangements and 
casualties that may occur in coal-burning plants, there are in addition a 
number of casualties which are peculiar to the former installation. 

A ilarabaok is due to the explosion of a mixture of oil vapor or gas and air 
in the furnace. Such an explosion may cause grave injury to the personnel 
and serious damage to the boiler, its fittings and attachments. A flareback 
is most apt to occur when lighting up, or when attempting to relight a burner 
from a hot brick wall. 

FreeautiOBS to Preirent narebacks. (1) Oil must nol be allowed to sceumulsta 
in the furnaoe. AH oil on the f arnaoe floor must be wiped up and the fumaoe blown 
through with steam or air before lighting the burners. 

(2) Whenever a burner is extinguished, shut off the oil and blow through the ftunaoe 
with steam or air before relighting the burner. 

(3) Never attempt to relight a burner from a red-hot brick wall. 

(4) Atomiter control cocks or valvee must be kept tight at all times to prevent leak- 
age of oil into the furnace from dead burners. 

(5) The firemen handling the torch in lighting burners must stand well elear of the 
register to avoid injury in case a flareback occurs. 

Prooedure When Vlalrebatik Oeeors. When a flardsack ocoun, elose the master oil 
▼aire, shutting off all oil to the furnace. Speed up the Mowers, if in operation, keep 
flreroom hatches closed, and stop the oil-service pumps. 

Firot. In each fireroom fitted for oil burning there shall be provided 
fire-extinguishing apparatus, consisting of steam fire hose permanently 
coupled and of sufllcient length to reach all parts of the fireroom, and either a 
box containing about two bushels of dry sand with a large scoop, or chemical 
fire extinguishers of the tank type. 

Do not allow oil to accumulate in any place; particular care must be taken 
to guard against this accumulation in drip pans under pumps, in bilges, in 
the furnaces, and on the floor plates. Any oil spilled must be at once wiped 
up. Whether at sea or in port, bilgee should be steamed out every watch 
and should be washed and pumped out at least once each day. 

Although smoking is permitted on the fireroom fioor plates in front of the 
furnaces by the Naval Instructions, in view of the possibility of carelessness 
on the part of the personnel, all smoking in the firerooms is generally 
prohibited. 

Proeedure In Case of Tire. In attempting to extinguish an oil fire never use water, 
as the only effect will be to spread the flames over a larger area. Fuel Oil is difllcult 
to ignite in bulk and is not capable of spontaneous combustion. There is little danger 
of the oil in the tanks becoming ignited, but in such an event steam hose connections 
should be made to the tank and steam turned on to smother the flames. 

In ease <rf an oil fire in the bilges, olooe master oil valve, shutting off oil to the burners; 
stop the oil pump; connect up the foam fire extincuisher and steam hose and direct the 
hose streams on the fire to smother the flames. If the fire be extensive, and the per- 
sonnel should be driven from the fireroom, all hatches, ventilators, or other openinv 
into the compartment should be closed and steam should be turned into the oompart- 
ment to smother the fire. 

If the blowers are in operation, judgment must be used in deciding whether to keep 
them in operation or to immediately shut them down. They will feed air to the flames 
and thereby aid combustion, but conditions may occur when speeding up the blowers 
may be the one thing that will save the personnel by giving them an opportunity to 
ese^ie. In gsnersl, the blowers should be secured as soon as possible. 



' 



PRECAUTIONS IN MANAGEMENT 



327 



Foamii* Firefo«m Method for Irtincntobtng Wit: In this method 
the fire is smothered by the application of Flref Oftm, a tou^h blanket made 
up of bubbles of carbon dioxide gas. This blanket will adhere to any material 
and float on the surface of gasoline, fuel oil, and all other inflammable liquids. 




Fio. 45. — Firefoam Sprinkler System for BUtinquiahing Oil ViTea. 



Th« aztliMrulshlnf medimn, ctrbon dioxide, is held directly on the bum- 
ing surface to the exclusion of all air and cannot be blown away by the wind or 
fire draft. 

Firefoam is generated by the mixture of two solutions which react upon 
each other and expand to a voltune from six to eight times the combined 



328 OIL FUEL BURNING 

volumes of the oriRinal solutions. The reaotioa evolves earboa dioxide, 
which, due to the presence of a foaming ingredient, Poamite, is not permitted 
to pass into the atmosphere but is held in the form of a blanket of foam and car« 
ried directly to the fire. 

Application of Firefoam. For incipient fires the Pirefoam can be 
applied by means of hand apparatut and Chemical engines which in 
outside appearance and operation resemble closely the ordinary types. 
In the protection of large oil bunkers of oil burning vessels and tank steamers 
the two solutions are pumped through a double pipe line which does not per- 
mit the two to mix until they reach the fire. Por the protection of the boiler 
rooms of oil burning vessels, the Pirefoam is applied by means of a Firefoam 
Sprinkler System. 

Firefoam Sprinkler System. Fig. 45 shows a Pirefoam sprinkler 
System for the protection of the boiler room of oil burning vessels. Prom 
the two solution tanks maintained under air pressure at all times, a double 
pipe line leads to sprinkler heads located throughout the boiler room and 
under the floor plates. At these heads the two solutions mix and Pirefoam is 
discharged. 

Operation. The system can be put into operation automatically by 
means of an auxiliary thermostatic system, or manually by means of controls 
located at a safe distance. 

Firtf oam Soluttoiui. Solution "A" is made up by dissolving aluminum sulphate 
in water; Solution **B" by dissolving bicarbonate of soda and Foamite in water. 

The percentage of concentration of the solutions varies with the different equipment 
in which the solutions are used. However, in every case, the determination is made from 
a computation of the relative weights of aluminum sulphate and bicarbonate of soda 
which will react chemically with each other. In the larger systems equal volumes of 
solutions are generally used; whereas, in the smaller equipment economy requires that 
the volume of the aluminum sulphate solution be reduced, a result which is accomplished 
by concentrating that solution. 

Solution **il." The proper quantity of water should be measured out and after the 
temperature has been raised to approximately 150 deg. the aluminum sulphate should 
be added slowly-~not dumped in — and the solution agitated for approximately five 
minutes. 

SoliUion "B." The proper quantity of water should be measured out and after the 
temperature has been raised to approximately 100 deg. but never above 110 deg., 
the bicarbonate of soda should be added and thoroughly dissolved, after which the 
Foamite, a thick black liquid, is added. At any temperature above 110 deg. the bicar- 
bonate of soda depreciates rapidly. For that reason every effort should be made to 
keep the water below that temperatiu^. 

Testing. The solutions should be t^ted for expansion approximately three times 
a year. Samples of the two solutions when mixed in equal volumes should give an 
expansion of from six to eight times the combined volumes of the two solutions which are 
used in the test. 

The solutions, with proper care, should last from two to three years. In some cases 
they have retained their efficiency for mdre than five years, but the life of the solutions 
depends upon the care exercised in their preparation and maintenance. Such conditions 
as high temperature and excessive agitation only tend to shorten their life. 

From a chemical analysis which should be made at least once a year can be determined 
what weight of the constituent chemicals should be added to restore the oiiginal efficiency 
of the solutions. There is a limit, however, beyond wMeh no degree of addtUon is 
effective. In that case fresh solutions must be supplied. 

Oil Leaks into 7eed-water System. Fuel oil may leak into the feed- 
water system through a leak in the oil heaters or through a leak in the heating 
coihi installed in the f uel*^!! tanks. Sueh leaks can be detected by ezamina^ 



PRECAUTIONS IN MANAGEMENT 329 

tion of the water drained from the steam side of the heater. Whenever 
leaks Kte found p the heaters must be by-passed; otherwise the oil will pass 
directly into the boilers through the feed-water system. The presence of oil 
in any boiler is dangerous, but it is particularly so in a small-tube boiler in 
which fuel oil is burned owing to the intense heat and the high rates of 
evaporation. 

Damage to Brick WftUf. Whenever a brick drops out in the furnace 
wall the boiler should be cut out, if practicable. If necessary to continue 
the boUer in operation until another can be connected up to replace it, 
burners adjacent to the location of the brick should be cut out to avoid 
damage to the boUer casing. 

Testing Oil System. Whenever 4hat part of the oil system subjf>ct to 
pressnre has not been in use for a period of a week, or after joints in the piping 
have been remade, it shall be tested cold under a pressure at least equal 
to the working pressure, and a careful inspection shall be made for leaks 
before fires are lighted. All fuel-oil fittings shall at all times be kept in 
working order; and the air slides, doors, and valves shall be frequently moved 
when not in use to insure that they are in good condition and ready for use. 



SECTION 4 



MARIMB BOILERS 

BY 

XUIXST H. PXABODT, M. X. (Stevens Institute of Technology), 
President, Peabody Engineering Corporation, Member Soc. Nav. 
Arch. & Mar. Eng., A.8.M.E., A.S.N.E.. H. A V.E.. Soc. Liquid 
Fuel Engineers. 

V 
CONTENTS 



Developmeiit 

Designation 

Ideal Requirements 

General Design 

Effect on Design of 

Fuel 

Draft 

Steam Pressure 

Steam Output 

Sise snd Number of Units 

Space and Weight 

Boiler Siaes snd Weights 

Design of Scotch Boilers 

Rules and Regulations Governing 
Boiler Construction 

Factor of Safety 

Hydraulic Tests 

Riveted Joints 

CftUdng 

Welded Drums 

Bumped or Dished Hesds 

Manholes and Handholes 

Cylindrical Shells, Riveted 

Flat Surface Stayed 

Stays 

Furnaces 

Combustion Chamber Girders 



Paox 
333 
339 
343 
343 



344 
344 
352 
354 
357 
358 
358 
385 



300 
301 
302 
303 
405 
406 
405 
408 
408 
410 
413 
415 
420 



Paob 

Combustion Chamber Tube Sheet 421 
Cylindrical Tube Sheets, Water 

Tube Boiler Shells 422 

Diagonal Ligaments 422 

Scotch Boiler Construction 426 

Tubes 434 

Boiler Setting 438 

Boiler Mountings 440 

Furnace Mountinjpi 453 

Superheaters 461 

Care of Boilers 

Preservation of Idle Boilers 464 

Prevention of Exterior Corrosion 464 

Raising Steam 464 

Removal of Oil 465 

Internal Corrosion 466 

Boiler Repairs 475 

Fuel and Firing 477 

Time Firing 47S 

Cleaning Fires 470 

Air Required for Combustion 480 

Analysis of Gases of Combustion. . . 481 

Removal of Scale 487 

Boiler Tests 488 

Boiler Materials, Inispection Re- 
quirements 514 



381 



iC 



MABINE BOILERS 

BT 

ERNEST H. PEABODY 

Serious ezperimentatioii in the propulsion of vessels by steam became active 
in the closing yean of the 18th century. Ingenious mechanisms driven by 
steam for operating oars and paddles were devised, soon followed by the use of 
steam-propelled paddle wheels. Considerable progress had been made on 
both sides of the Atlantio when Fulton brought out the first commercially 
BU coD O s ful steamboat, the "Clermont,** which was given her initial trial on 
the Hudson River in 1807. Colonel John Stevens, of Hoboken, had already 
built several very practical boats; and, many years in advance of his time, 
had developed a steamboat operated by twin screws which had a successful 
trial on the Hudson in 1804. The remarkable genius of Stevens may be 
appreciated when it is considered that not only did he adopt the screw pro- 
peller and twin screws, but he employed a gearing between the engine and the 
pfopeller-shaft by which one engine 

operated both propellers. Further- fp 

more, he developed a water-tube ^ 

boiler to carry 50 lbs. gage pressure, ^% 

an illustration of which is shown in <^sL 

Fig. 1. The boiler and propelling j" — — si^B ^ ^7™'~^^ 

machinery were built in his own I ITI ^^^^Si |£^S^ 

shops. He was already well ad- Ie^=3^=_J | ^-^4 ;^.>-HP^ >^[ ffrr^7r\ zd 

vanoed in the construction of a \ -— :::i^^ ~_„ =ii 

lareer vessel, the'* Phoenix, "operated Pio. i. — Stevens* Boiler. 

by paddle wheels, when the trial of 

the "Clermont," and the succeeding patent award to Fulton by the State 
of New York, giving him control of the waters of the Hudson, made it neces- 
sary for Stevens to take the "Phoenix** to Philadelphia. She thus achieved 
the honor of being the first steam vessel to make a voyage at sea. 

I\il ton's foresight in obtaining an engine and boiler designed by James Watt 
and built by Boulton A Watt, at Soho, Scotland (which he shipped to New 
York with the permission of the English government and installed in the 
"Clermont'*), no doubt had much to do with hi^ success in anticipating 
Stevens, the facilities for the fabrication of machinery being then much 
further advanced in Great Britain than in America. 

The early experimentors in steam navigation naturally adopted the prevail- 
ing types of stationary boilers, among which was the vertical type called the 
"hajstack" boiler from its resemblance in shape to a stack of hay, and the 
borisontal "wagon" boiler of Watt, named from its resemblance to the top 
of a wagon of the "prairie schooner" type. Smeaton conducted some inter- 
esting experiments on shore, at Long Benton, England, in 1772, with the 
"haystack" boiler fitted with a flue and carrying a pressure of l3^ lbs. above 
the atmosphere. The boiler of the "Clermont" was of copper, about "7 ft. 
deep and 8 ft. broad" by 20 ft. long, set in brickwork, and carried a pressure 
of 5 lbs. above atmosphere. It was provided with one square-section return 
flae running the entire length of .the boiler, the grates being installed at the 
front, and the hot gases passing to the rear under the bottom of the shell and 
back through the flue to the funnel. 

333 



334 UARIKF. BOILERS 

The natural developmeDt of the marine boiler was first along the line of 
iDodiScationa of the "wagon" boiler, with shells made square or with Bat 
rides and rounded top. and with various arrangemeDts of recUmgular flues 
with various twists and turaa, and elso with flues of circular and elliptical 
eection. A boiler of the flue type, carrying a pressure of 15 lbs. persq.in., waa 
installed in the S.S. "Sinus" in IS3T. This vessel was one of the first to 
make a trana-AUantic voyage entirely by steam power. 

Within the following ten years the next development began to be Intro- 
duced, consisting of the substitution of tubes for the rectangular and round 
sheet flues. Fire tubes had already been used, notably by Stephenson in 
the locomotlTe tMiler of the " Rocket." in 1830, but the introduction of 
lubes in marine boilers had beeuBlow, and it is interesting in aoM that so late 
as 1S62 a lively controversy was under way as to the relative merils of 
the flue bailer versus the tubular boiler. We even find vessels DODStruct«d 
in the fifties fitled partly with fiue lH>ileni and partly with tubular lioileis, the 




Flo. 2. — Stimer's Return-tubular Boiler. 



designers evidently being reluctant to trust themselves entirely to the fire- 
tube construution. The same thing has been witnessed in our own day, 
where vessels have been fitted partly with Scotch boilers and partly with 
water-tube boilers, on the same reasoning. 

The steam pressures carried in 1S50 vere surprisingly low. A list of sixty- 
four vesBols (most of them Boa-going) fitted with boilers designed and built 
in America shows that (en of them carried 10 to 12 lbs. gage pressure; twenty, 
13 to IS lbs.; Ave, lSlo20lbe.; sii, 23 to 25 Ibe.; seven. 28 Co 30 lbs.; five. 32 to 
35lbe.: five, 36 to 40 Ibe. ; throe, 45 lbs. : one. 50 lbs.; one. SO lbs. and one, 90 lbs. 
Thus, more than half of these vessels carried pressures of 20 tbe. and under, 
while 53, or S4 per cent of the total number, carried sicsm prn.ssurcs not over 
35 lbs. Most of these boilers were of the circi;lar-flue type. Some hod shells 
of approximately square section, others oval; and a oonaiderable number 
cylindrical, this being the cose with all types carrying 30 lbs. and over. The 
return-tubular idea was well represented, the type shown in Fig. 2 being a 
typical example. This boiler was invented and patented by Alban C. Stimera, 
afterward Chief Engineer of the famous " Monitor" in the Civil War. The 
highest presBure of lil (00 lbs.) was that of a vessel operating on Lake Erie, 



DEVELOFitENT 336 

whcwe boilers eooButed of sereo iron cylindrioal Bhella, 30 in. in dlametor hy 
^>ont 24 (t long, each fitted with two Vi in. diameter return Buee, Fig. 3. 
Thmr boilen were set on deok, the total lieating lurface being 3640 gq. ft. 
and the total ffaXe surface 1 12 iq. ft. One of the anomaliea of steam naviga- 
tioo i* that thia type of boiler baa prevailed to the present day, and is now in 



front of Bflile™. 




Crosa Section. 
Flo. 3.— Early Inland River Type B 




— S. S. MttcGr^gor Laird Boiler. 



a uae oa inland rivera wiiere muddy river water is used for feed and 
wbeM the ease with which the boiliv may be wanhed out every few days ei- 
plsiua the oommon use of the design. 

Id ISeS, the boiler shown in Fig. 4 was fitted in the S. S. "MsoGregor 
Xi*iid." Tliia haa been referred to by writers ae the Brat example of the 



336 



MARINE fiOIL£R8 



Scotch boUcr. However, previous to 1851, the boiler illustrated in Fig. 5 
was designed by an American engineer, Mr. ErastUB W. Smith, and con- 
structed by Mott A Ayree, of New York, for the S.8. *' Hermann." This 
boiler was fitted with a steam-dome through which the uptake passed (some- 
times called a "wet uptake"), and the front tube-sheet was set back from 
the end of the boiler, both of which characteristics while not now in vogue 
were not uncommon in early designs of the Scotch boiler. It api>ears, there- 
fore, that America may well claim the honor of having produced the first of 
this celebrated type. 




Fio. 5. — Smith*8 Boiler. 



The compound engine, first suoceosfully introduced by the progresaive firm of Ran- 
dolph A Elder (also builders of the "MacGregor Laird"), in the S.S. "Brandon." in 
1854, had much to do with the gradual working up of steam pressures, as it was dis- 
covered that compounding was of little value unless accompanied by higher pressures 
than the then favorite 15 to 20 lbs. However, 35 or 40 lbs. was considered good enough, 
and the attention of marine engineers at this time (the late fifties) was taken up with 
the problem of improving the economies by increasing the temperature of the steam by 
superheating rather than by a material increase in pressures. The 8Ui>erheater continued 
to be used ulitil the early seventies, with pressures up t^ 60 lbs., when difficulties with 
lubrication and trouble with the superheaters themselves led to their abandonment for 
the time. 

In 1874, the triple-expansion engine was introduced by Kirk, in the S.S. "Propon- 
tis," and proved a still further incentive toward higher steam pressures. It is a com- 
mentary on the conservatum of the marine engineering of the day that as late as 1875 
there were many advocates of the simple as opposed to the compound engine, and that 
serious consideration was even given to the project of designing the propelling machinery 
of war ships to operate at pressures of 15 lbs. abs. (atmos. press.), that is. depending on 
the vacuum, so that in the case of a boiler or steam pipe being perforated by a shot, the 
steam would not rush out and injure the personnel. 

Within the period of twenty years from 1875 to 1805, the triple-expansion 
engine fully established its superiority over the compound type for sea^going 
vessels The type of boiler also became settled, the Scotch boiler, with its 
circular shell and convenient return-tube arrangement establishing a reoo^ 
nized superiority over the earlier flue construction. These two facte, accom- 
panied by the introduction during the same period of open-hearth steel plate 



DSVBLOPMBNT 



337 



for boiler mftnufacture, account for a very remarkable inoreaae m vteam 
preflsures. In 1876, the prevailing practice was represented by 60 to 80 lbs. 
per sq. in. In 1895, it had risen to an average of 160 to 165 lbs. (required by 
the triple-expansion engine), with a few instances of pressures as high as 
180 lbs. This rapid increase in working pressures is all the more remarkable 
in view of the slow development toward higher pressures in the preceding 



Meantime, it is interesting to note the development of the wateir-tube 
boiler. The great flexibility of this type early led to the introduction of 
freak designs, inaccessible for cleaning and repair, and which, on account 
of high steam pressures and defective design in numerous instances led to 
disastrous results. A successful design by John Faron was, however, in- 
stalled in the trans-Atlantic steamer ** Atlantic," in 1849, followed by similar 
instaUations in the "Pacific," "Baltic," and "Arctic." Fig. 6. The fuU ad- 
vantages of the water-tube principle were not realized in this boiler, as it did 








Fig. 6. — Faron's Boiler. 



not eliminate the large semi-rectangular shell; and the design gave way to 
the superior features of the cylindrical boilers of the flue and fire-tube type. 
In 1851, Belleville began the interesting development of the boiler which 
bears his name. He was' followed by Lagrafel, Niclausse, Du Temple, 
Thomycroft, Yarrow, Cowles and others, some of whom produced designs 
which have survived. In 1893, a water-tube coil boiler, designed by Charles 
Ward, was instaUed in the U.S.S. " Monterey," under the initiative of 
Admiral George W. Melville, who during his period of service as Engineer-in- 
Chief of the United States Navy from 1887 to 1903, took a prominent part 
in the famous "Battle of the Boilers" which led to the ultimate elimination 
of the shell type of boiler from aU fighting ships and the substitution of water- 
tube boilers. 

The first Babcoek A Wilcox Marine Boiler was designed by Stephen Wil- 
cox, and installed in the yacht " Reverie," in 1889. This design was improved 
and perfected by William D. Hoxie, who in 1895 brought out the "Alert" 
type (so called from the fact that it was first installed in the U.S.S. "Alert"), 
Fis. 7. This boiler, owing to its simple, effective design and acoessibiliiiy, 
and the fiMst that it is constructed entirely of forged steel pressure parts» 
straight tubee and expanded joints, and its adaptability for working pressures 
of 250 to 300 lbs. and over, has had phenomenal suooess in naval vessels and 
m the merchant marine. 

The World War,' now dosing, has resulted in a greatly extended use of 
water-tube boilers in cargo and merchant ships, the most successful of the 
▼arious types being designed closely along the lines of the Hoxie patent. 
Many of these vessels have also, with marked success, been fitted with fuper- 
Itafttan, the modem type of which was re-introduced into marine practice 
22 



338 MARINE BOILERS 

by The BKboook A Wiloox Compuiy in the Lkke steBmer " D. G. Esit," in 
1902, and in the U. 8. Navy in tbs U.S.S. "Indiana." in 1004. Specially 
daajgnad miperheatcn are aim beiog extensive fitted in Sootch boilen, tb« 
objsctiona which led to the eliminatioTi of the earlier typee of superbeatAn 
having been entirely overoome. 

The advantages of high prcniiure and iuperhe«(«d Bteam have Ions been 
recogniied by marine engineers. Superheat, as noted, is again being adopted; 
and whUe to KHae extent quadnipln-eipannon ensinw led to the use ot pres- 



Fio. T.— Babcock & Wilcoi Boiler, " Alett Typo." 

aures of 260 ibe. with well-dedgned watar-tube boiten, the iocrean in steam 
prenuree has not been at all rapid ainee 1896. The common presmiree to-day 
(19IBI fornewwoTkmaybe considered as IBO Ibt. for Scotch boilen and 200 
to 210 the. for watet^tube boilers. The introduction of etcam turbines baa 
been partly reaponaible for this slow increoiie in preBaures, recent development 
having been more along the lines of improved vacuum father than toward 
higher working pressures. It is probable, however, that neoeeaity for in- 
creaMd eoonomies and reduction in weights will again remit in the upward 
climb of working preseurea for which the water-tube boiler is exceedingly well 
adapted. 



DBaiONATIOH OP BOILERS 

DISiaXATION or BOIUE8 

Mmiim Boilers are deosnatod in different wayi, uioordinB tc 
Mll-avldBiit chkracteriatics. 



||l 

ill 



I 



I 



tbe wBter pewea tl 



340 



MARINE BOILBRS 



Fire-tube boilers are those in wbich just the opposite takes place, fire passing 
through the tubes which are immersed in water. 

2. Bztemally Fired and Internally ^Fired. Externally fired are those 
in which the furnace, while within the boiler setting, proper, is external to 
the heating surface of the boiler. Most water-tube boilers come under this 
class; also fire-tube boilers of the tj^pe in which the gases pass first under the 
shell and then through tubes or flues. Watt's "wagon" boiler and the hori- 
sontal return tubular (land type in brick setting) are examples of this con-> 
struction. Internally fired boilers have the furnace practically surrounded 
by the heating surface, such as in the Scotch boiler, locomotive, leg type, etc. 

5. Tubular and Tiibulous Boilers. In this sense tubular signifies fire- 
tube boilers while tu bilious is a term formerly given to water- tube boilers; 
the latter designation is now not much in vogue. 

4. Single-end and Double-end. Boilers fired from one end or from 
both ends; the term usually refers to Scotch boilers, the double-ended boiler 
being [iraotically two boilers combined in a single shell, the back heads being 
omitted. 

6. Wet-baek and Dry-back Boilers. A wet-back boiler is an internally 
fired boiler in which the back of the combustion chamber is formed by a water- 
leg or water space between two flat stayed surfaces, the water l^ng comprised 
in the main .circulatory system of the boiler and under pressure. The term 
dry-back designates the type in which the back of the combustion chamber ia 
formed by fire-brick, usually backed by non-conducting material and a sheet- 
metal casing. (See Fig. 8.) 

6. Flue Boiler. A fire- tube type in which the gases pass through rec- 
tangular- or circulai^ or oval-section flues. The distinction between a flue 
and a tube is usually fixed at about 5 in. diameter. The term "tube" is used 
when the diameter is 5 in. or less, and the term " flue" is used when the 
diameter is more than 5 in. 




Fig. 9. — Gunboat Boiler. 

7. Drop-flue Boiler. — An arrangement of flues by which the gases pass 
into the upper flues first and drop down to the lower rows in passing to the 
uptake. This type saves some headroom over the ascending-flue boiler, 
in which the gases enter the lower flues first. 

8. Borisontal Return Tubular BoUer. The horisontal fire-tube type 
in which the gases pass to a combustion chamber in the rear and then return 
through tubes to the uptake at the front of the boiler. The term usuiUly 



DESIGNATION OF BOILERS 341 

refers to the ezienudly fired dry-baok boiler, set in brickwork, of a type 
similar to the "Miasiasippi River" boiler. This type is not much used in 
marine practice except on river steamers. The return-tube construction, 
however, is ezemplificKi in the Scotch boiler. 

9. Scotch BoUor. — This boiler receives its name on account of its popu- 
larity with shipbuilders on the Clyde. It is of the cylindrical-shell, inter- 
nally fired type, fitted with corrugated furnaces, wet-back combustion chamber 
and return fire tubes. The cylindrical furnaces, which contain the grate- 
bars, bridge-wall, etc., are corrugated to give strength against collapsing 
pressure and to provide for longitudinal expansion and contraction. 

10. Gunboat Boiler. The cylindrical fire-tube type in which the diam- 
eter is made relatively small to reduce headroom, the boiler being increased 
in length to give the necessary heating surface. The tubes, instead of re- 
turning from the combustion chamber to the front of the boiler, continue on 
to the back, where the uptake is situated. (See Fig. 9.) 

11. LocoxnotiTe Boiler. The locomotive boiler as used in marine prac- 
tice is an application of the standard locomotive type to river steamers 
and also to light-draft high-speed vessels. It has been entirely displaced 
in that service by watei^tube boilers, but for a time was employed on ac- 
count of its comparatively light weight. This type met with considerable 
success in some of the early British Destroyers. 

11. Leg BoIImt. The internally fired boiler in which the furnace walls 
are constructed of fiat stayed-surface water-legs. This application is usually 
made in connection with cylindrical shells fitted with fire tubes, as in the case 
of the locomotive boiler, which is an example of the type. 

15. Shell Boiler. The fire-tube type of boiler in which a large cylindrical 
shell is used under pressure, as, for example, in the Scotch boiler, as dis- 
tinguished from boilers of die water-tube type, which use small-diameter 
Bteam-and-water drums. 

14. Flre-boz Boiler. A boiler in which the furnace is located in a so- 
called ' ' box' ' of flat surfaces which form the furnace walls. It is similar to the 
Locomotive and Leg boilers except that it has return tubes. 

10. laObeterback Boiler, Fig. 10, has a cylindrical shell; box-shaped fur- 
naces with water-legs at one end of the shell; flues leading to the back connec- 
tion and return flues or tubes to the funnel, which is located about midlength 
of the boiler. This type is adapted to go under deck in shallow river boats. 

16. Sxprees Boiler. A term used to designate very lightly constructed 
water-tube boilers fitted with tul)es 1 in. to IH in. in diameter, which may be 
highly forced. This is the common type for Destroyers and very high-speed 
vessels. 

17. Coil Boiler. A boiler of the wateivtube type, in which the tube is in 
the form of a coil, usually in the form of a portion of a helix. 

18. Porcupine Boiler. A vertical shell from which water-tubes of the 
Firid type extend on all sides, like the quills of a porcupine, and around which 
the gases pass as they ascend to the uptake. The Field tube, invented by 
Pield in 1866, consists of a tube having one end open to the circulation and 
the other closed, and another tube of smaller diameter inside, so arranged 
BS to deliver water to a point near the closed end. 

19. Hash Boiler. A boiler containing little or no excess water, and 
liaving no water line, and in which the feed water is injected in amounts 



GENERAL DESIGN 343 

sabstantially equivalent to the demand for steam. Tbk boiler takes its 
name from the fact that the water flashes into steam almost immediately on 
entering the boiler. The type is attractive for marine purposes on account 
of the reduction in weight due to the small amount of water carried. It 
has. so far, however, not been successful in any but very small units. 

90. Sectional Boiler. One in which the water spaces are divided into 
small parts, none of which is subject to disastrous explosion. This is an 
essential feature of "8*fety" boilers. The term "Sectional** is sometimes 
UBsd to designate the vertical divisions of the tube-bank of certain classes of 
water-tube boilers, but this point has been adjudicated, and the meaning held 
to be that of the broader definition given above. All water-tube boilers are 
therefore sectional in character. 

SI. "Pipe" Boilers. Those made of pipe through which the water 
circulates. Frequently used to designate all characters of water-tube boilers. 

The infinite variety in which water-tubes can be 0'ouped, bent and interlaced, renders 
the term "watsr-tabe" altofether too broad to be used to designate a type. 
A wBter-tnbe boiler of robust struoture, built of forged-eteel pr«taure parte, straight tubes 
and ejqMUMied joints, is much nearer in its salient featufes to tiM Booteb-botler class than 
to the type in which small bent tubes or screwed pipes are crowded into small space with 
little furnace volume, no combustion chamber and inadequate baffling. The latter 
type is inaccessible and uneconomical and is foredoomed to failure in severe service, 
while the former is able to meet the most strenuous demands and is safe, economical, 
and approximately half the weight of the Scotch design. This type of water-tube 
boiler ia destined to supplant the excessively heavy, unsafe and expensive Scotch boiler 
in the merchant marine as it has already done in naval service. 

IDBAL BBQUntBMBNTS FOB MABIKB BOILBBS 

Ideal requirements for marine boilers may be summarized as follows: 
ability to carry high' pressures without danger of disastrous explosion; 
accessibility for readily cleaning and overhauling all parts; lightness and 
compactness so as to "stowtj* well on shipboard; efficiency and economy in 
fuel consumption; simplicity of design and avoidance of special features 
which complicate repairs and necessitate a large stock of spare parts. 

The late Rear Admiral Oeorge W> Mehille st-ated that it was his conclusion 
that the thoroughly satisfactory water-tube boiler should possess, among 
others, the following characteristics: Reasonable lightness, with scantlings 
sufficient to promise reasonable longevity; an adequate amount of water, so 
that failure of the feed supply or any inattention thereto would not imme- 
diately cause trouble; accessibility for cleaning and repairs on both water 
and fire sides; straight tubes, with no screw joints in the fire but the simple 
expanded joints so well tested out for years; no cast metal, either iron or steel, 
subjected to pressure; ability to raise steam quickly; high economy of evapo- 
ration; economy of space; interchangeability of parts, and, as f ar as ];>ossible, 
the use of regular commercial sises, so that repair material could be procured 
ansrwhere; the ability to stand severe forcing without injury; the ability to 
stand abuse; that is, to be of rugged construction and not so delicate as to 
require skilled mechanics to run it; safety against disastrous explosion, mean- 
ing that only the part of the boiler which gave way would be damaged. 

OBNXBAL DBSIOK 

The factors which determine the principal features of boiler proportions 
And design are (1) kind of fuel, (2) draft, (3) steam pressure, (4) steam output, 
^S) size and number of units, and (6) available space and weight. 



344 MARINE BOILERS 

1. Kind of Fu«l, IS«ct on ]>«8ign. The first requirement in generatins 
steam is to properlsr consume a sufficient amount of fuel. There is no use 
in adding heaUng surface if the necessary heat cannot be generated in the 
furnace. This simple axiom is oddly enough often overlooked. The boiler 
furnace is therefore the starting point in any calculations on the production of 
power by steam, and obviously the kind of fuel qualifies the fujrnace desisu. 
The character of the fuel further has an influenre on the proper arrangement 
of the heating surface, and particularly on the baffling of the gases and areas 
of the gas passages, those fuels which can be burned with smaller- amounts of 
air for combustion. requiring smaller gas passages and smaller uptake areas. 
Volatile fuels such as oil or volatile coals require larger furnaces. If smoke 
and soot and ashes are produced in combustion, the necessary .cleaning 
facilities will bo required. 

S. Draft, Kflect on Design. Whatever the future may hold, atmos- 
pheric air is now the universal means of supplying the necessary oxygen for 
combustion. The rate ^t which this air is supplied depends on the intensity 
of the draft. Natural draft, so called, is the suction produced by the funn^, 
and the intensity of the draft depends mainly on two things, (1) the 
temperature of the escaping gases and (2) the height of the funnel. The gases 
must leave the boiler at a temperature not lower than the temi>erature of the 
steam. They should not exceed this in a well-designed boiler by more than 
100 dcg. F. to 200 deg. F., depending on the rate of driving. As the tempera- 
ture of steam at 200 lbs. pressure is 388 deg. F., this would make the 
proper uptake temperature approximately 500 deg. F. to 600 deg. F. They 
frequently, however, reach a temperature of 800 deg. F. to 1000 deg. F. in 
some tyi>es, a condition which is promoted by neglect in clea&itig the boiler, 
leaky baffles and insufficient or inefficient heating surface, etc. If the waste 
gases are increased from a temperature of 500 deg. F. to a temperature of 
800 deg. F. the effective draft at the base of a 100-ft. funnel will be increased 
from approximately 0,47 to about 0.63 in. of water. 

The influence of the wind is an importanf factor in creating draft, this 
effect being practically independent of gas temperature and funnel height. 
A good head wind will increase the draft a tenth or even two-tenths of an 
inch of water column.' The effect of the wind becomes negligible when the 
wind is "following" the ship and blowing at the same rate of speed; and as 
this condition may be frequently met at sea, the designer must provide for 
this condition, any gain due to favorable winds being merely that much 
margin in securing good steaming conditions. 

Draft intensity is due to the unbalanced pressure of the weight of the heatod 
column of gas within the funnel and the weight of a column of cool air of 
the same height outside the funnel. Thus, the temperature of the outside air 
is another factor in draft intensity, cold air giving a higher draft than warm 
air. This, however, may be ignored in the design, as the change is slight and 
is partly balanced by the check to combustion due to the chilling effect of the 
cold air on the furnace temperature. Barometric pressure is still another fao- 
tor in creating draft intensity, a low barometer gi\dng less draft than a high 
pressure. At sea level this difference is negligible. 

If the various data are available, the draft that will be obtained theoret- 
ically may be determined by the Peahody Draft Formula which was 
devised by the writer as a means of simplifying the calculation: 



/ 8260 aeeo \ 



HB / 8260 
100 



DXSinN— DRAFT 



34fi 



D •• Dnit in hoitdMdUM «f ui inoh water ooliutui; 
H — Heigfat of tunnel In feet above point of draft n: 
B — BeromeleT reading in inchsB of mercury; 
I — Temperature of outside air, deg. F.; 
T ■> Temperature of gaaea inside funnel, deg. F. 

TIm effect of friction, gae eddiee, the cooling effect of air Isalca^, etc., 
(omhina to reduce the intensity of the draft obtained in practice, so that the 
thnretieal resuits must be multiplied by a variable coefficient (depending 
upon tLe conditions} to obtain the actual draft at the base of the funnel. 
A eoeSnisnt Of O.S tepreeente foiriy average practice. 

The following handy rule will be nearly enongh correct to serre in the large 
nijarity of caaes: The actual draft intetult^r «k- _ 

pTMMd in bundrttdtlu of ut in«h of w^Ur oolumn 
•tthi bate of tunnel or In the uptake at the boiler 
tamper will be approximately equal to oiM-h^ 
Itw *«itleal dlBtonce In feet from tho point of 
■MomremMit to the top of funnel. 

When the draft intensity is increased by means of fans 
or blowers it is called Toroed Draft. It is' evident from 
fu above draft formula that any desired draft intensity 
■uy be obtained if the tunoel can be made high enough. 
Thus, a tunnel, say. 300 feet high would give B draft, at 
ltd base, of approximately lii inches of wat^ column. 
Bueh dimeasions are of course prohiliitive on ahipboard, 
sad blowers are reeorted to to give these higher drafts. 
Tben is, however, no real physical difference between 
Inesd and natural draft, the distinction being limited 
to the means of production. 

CsuidFrina draft IntenutT M  difTtveDM in tu pmeure, i 

•"■B- prfHun wbether (hi* diHerenc* in pr««urB be produned 
Mtonlly by  funnel or BrtifiaiBllr by ling, la olbfr words, 
f^<R  bo real distiwrtioo bctwnen a poah uid a pull, except 
>> <>■■■ wbcTE t)>e fareed drift is applied to tbe sibpit only 
{MiiUiecaH of ashpit draft) uutaad of (hs enljra Kttiii(. 
uiolheiaH oCcltaedaraoom, atn. In that event, the pressun 
)■ Ilie uhpit being higher than the pnsure srouni! tbe boiler 
"'H. lay slight leakiga in the latter affects the coure* o( the 



■1 naE(7  combinatii 
^■A unwires (that i 
Oefgd. 

Id ddq4 this certain 
^rfu* ind through thi 



that a luDOal must always be provi 
s gam, the (oreed-draft iastallitio 
n of forced and natural draft, sad 
. the aUebi-aii] difference) that ii e 



ided 



ir, in the case of oil fuel, through the mtrioled open- 

''■ft measured Id the boiler furaaoa, or the difference between the furnue pressure 

*»ft intensity u niMsured by  drift ssie is greatly affected by the rtsiatanre the ur 
*Mtt b getting into tbe furnace. For eiamiile, in the case of a coal fin, if the fuel 

asDi irhtle the a|>iJ*iTeDt fitmact draft as measured by gage is at its minimum. As the 
he bed builds up and beooma choked with cUskei, the combuitiDn rale falls off, but 
Ae fu/Tiice draft incressfB- 

The lune thing la true of the draft as measiuad at the uptake or bollar ilainpar, 
tat 11 tha point tbe ehangte ire less marked for the resson thst the friction through 



346 MAHIUS BOILBRS 

Ui« bdlar U Hided to thM at th* trletioD of th* (MM mtmiat tlw ttuiueo ftod tlio p«r- 
nnUf* of chuifl* wHb vaiyinc An bed oondltioiH ia (rHtlr nduoad. While Uu Irie- 
tion of the seeee Ihrouih e boiler eetlinc vena eomewbmt with tbe nte of fordiic, 
d«ign end type of the boiler end the proportion of heeliDE Aurfiwe to crete eurfeee, 
these cheagee ere leei importeat Ihui the ohengKl reaieunce of the Sre bed and its 
erratic eflect on the draft cage. For theee re»80D>, the writer believea that (t i> more 
pmotioiJ to bee* etlcuUtiooi oa draft differenae betmen the tipiakt and the fireroam 
rather than betweeo the fireroom aikd tbe fumaee. TIbe fireroom preeeure a used Inetead 
of the aehpit preaaure* ai at hish rmlm of foroLoc there ie a ilicht drop ia preHure in tbe 
pMiuic* of tbe ur tbroush the aah-doon. 

Tbe foUowing rwuita were obtaiaed in a luge oambor of twtc, trtal 
trlpB, etc., t¥ith Baboook A Wilooz MMute Boilera, with seini-hituiniiiouB 
mine-ruii oool, h&nd fired: 
Draft B»4iuiwd »t DUtwMit Kat— of OombTiitton 



fliwoom, Toohea 



Draft raouind. 
DifTeienoe betmea 
boiler damper and 

fireroom, Inidte* 



Cool per Square Fool- otinH per Hour in Pound* 
Fm. 12. 

These Gfurea are reprmented eraphically in Fis. 12. It ia t 
thia chart may be lued for forced draft aa well as natural draft, i 
iodicate the algebraic difference between draft prSMures ia 
the outlet from the boiler and the fireroom. 



) be noted thai 
ls the ordinatoe 
the uptake ^ 



OENBSAL DEaiGN-^DRAFT 847 

foTMd draft for inoreasing the rste of oombintion may be Tariouely ap- 
plied. In the Oloied-Mhpit aRangemeoi, the blowers foroe air under prea- 
mue to the aahpit, which is made as far as practicable tight against the passage 
of sir except through the furnace grates and the five bed, thus accelerating the 
combustion rate. In this combination the relation of the draft pressure to 
that of the atmospheie becomes a vital factor. The natural draft or suction 
is a minus pressure (i.e., below the atmospheric pressure), while the pressure 
in the ashpit is a positive pressure (i.e., greater than the atmosphere). The 
pressure around the boiler setting remains the same as the atmosphere. The 
aeatral point in the passage of the gases at which the pressure changes from 
plus to minus («.e., becomes equal to the atmosphere) depends upon the 
amount of the natural and forced draft, and also on the resistance of the fire 
bed and the boiler. Thus, with a strong natural draft and a low ashpit 
pressure, this neutral point may be in the fire bed itself, and the furnace 
pressure will be minus. Under these conditions, when the fire-doors are 
opened, air flows into the furnace. , But if the ashpit pressure is increased or 
the suction lessened, the neutral point may pass on into the boiler paasagesv 
or even into the uptake, in which case there will be a positive pressure in the 
furnace. Then when the fire-door is opened, the hot gases wiU blow out into 
the fireroom and this may reach a point where the fires cannot be handled 
properly. Under these conditions, the ** blast" in the ashpit must be shut 
off or reduced temporarily while the fires are being charged or sliced, and 
turned on again when the fire-doors are closed. Automatic devices for shut- 
ting off the forced draft when the fire-doors are opened are frequently em- 
ployed with ashpit draft. 

An ingenious method of reducing the tendency for hot gases to blow out 
the fire-door is to admit a portion of the air directly to the furnace over the 
file bed through jets around the fire-door opening. These jets discharging 
toward the rear, create a flow of air inward through the fire-door, thus oppoe- 
ing the hot gases that tend to flow outward. This device is effective to a 
limited degree in enabling higher ashpit pressures to be carried than would 
otherwise be possible. 

Under usual conditions on shipboard, where ashpit draft is used, it is found 
that about 0.5 in. or 0.75 in. in the ashpit can be carried without interference 
with the firing. Above this pressure, the blast must be closed down each 
time the doors are opened. High forced draft on the closed-ashpit system 
has the objection that any slight gas leaks in the furnace or boiler setting will 
peiinit hot gases to escape outward under the effect of the plus gas pressure. 
This increases the wear and tear on the setting and causes added heat and 
discomfort in the fireroom. 

Tbe Balaneed-draft system is a method of proportiomng the sahpit and snction 
draft ple a su re to give a negative or a very etight positive preeaure in the furnace at all 
filmea. There is a patented device for doing this automatieally, and it is claimed that 
an improvenacnt in economy and longer life to the setting is oeoured, as the furnace 
temperature is not lowered by the inrush of cold air on opening the fire-doors and the 
temperature of the casing and setting remains at a constant and moderate temperature. 
The rate of combustion is limited with this system, and it has not been extensively 
employed in marine work. 

Forced draft on the Closed-fireroom system consists of making the entire 
Breroom and stokehold tight against air leakage, and forcing air into this 
^paoe under pressure by means of blowers, usually located outside the com- 
IMrtment. Deflectors are frequently employed at the blower discharge for 
yreventing the rush of air into the fireroom, and diffusing it. This is par- 
iculaziy necessary when the room pressure is high, as in the case of naval 



i 



348 , MARINS B01LEB8 

work with aH htA, whara pre — nrw of 6 in. to 8 in. ara MHplfq^. - In ^in 
okM. tha lou of beftd due to veloct^ of tiie Kir ii an inportatit feBtun and 
demands more study in the luTBngemeDt and farm of sir duct« than the 
problem usiiBlly reoeivee. Cloned-fireroom fon!«d draft has all the lulvantfteai 
of natuTBl draft, barring the iLinonTemaDoe due to the QocoBdty of providing 
all eatrance and exit doors with air locks, i.e., veatibulee with double doon. 
The rat«i o( oombuation. which may be obtained are, bowever, limited 
only by the ability to handle the fires, and tliere is no blowing out of hot las 
fn>(D the Sre^oors or settias. all tfae flow being inward, as the higher [ir t mu re 
ia alwaj^ in the firorooDi- Tickt b«ller iHWiBfm are a neoeadty, however, 
and there ia some lose due to cold air enlwing the furnace door when open. 

Induoed draft is the syst«in of forced draft which conitiste of the applics- 
tion of large blowers designed to draw the hot gasea Out of the uptahee and 
dlBcharge them into the fonnel, a damper being employed in the uptake to 
make certain that all the gasea flow throurfi 
the fans. This is equivalent in effect to 

high natural draft. The blower* are re- r- 

quired in this case to handle hot gases, but I 

for moderate rates of forcing the scheme is > 

eSectiTe. 

A system of induiwd drslt tanned the Piat 
Hector Draft Bysteio has also been devised 
whereby  Jet of eold air is dlschanced upward 
in the contra of the [nansl for tfae ptuitaa* of 
aceelerating the draft (uctioQ. This is s revival 
o[ an old idea, uid while efteBtive [or low ralsa of 
driving, it has not been widely used. 

StOMlt Jet* in the funnel or uptakos 
readily increase the draft, but unless prop- 
erly designed they are very wasteful of 
staam. and in any event the lo«a of fresh 
water renders this method of forced draft 
prohibitive except for baibor veesels. 
(See Fig. 13.) 

BMam jets may also be used for forcing air Into 
closed sshpiMt thus areatin^ a pisitive presserc 
iutcad of a suetion. This arrangement will Fiu 

emiTBrnny in™iurp. However, it hsii one partirular feature worthy of mention: Very 
ponr furls which run high in ash nnd tend to rnske  bad eUnker may be burned natis- 

eouU not b« employed with ordinary draft or whieh if u employed woald pre ODdy a 

VtntllKton. Although of utmost Importance, the noi-ossity of using 
TeDtilslom of adequate llae is often overlooked. Obviously, the air must | 
be delivered to the hrerovm before it can gel to the furnace, or, if forced-draft 
fans arc used to drive the air into the boiler room, the air must be delivereil 
to the fans through ducts of adequate sim. If the fans have to suck the air 
through restricted or circuitous paasagoa. or it the natural funnel-draft is 
called upon to aasist the air ut high velocity down small vontilntorB. very 
decided losses in capacity result; losses which could easily be prevented. 
This in especially true of natural-draft installations. Ventilators ahould tM 
lockted with cowls on dock in HinbslTTiclcd places so that they will get the 
air freely, and they should be carried down into the firerooma with as fev 



350 MARINE BOILERS 

henda as possible, and should discharge direedy in front of the hoiUrB, and 
low enovffh doum (not over 7 or 8 ft. from the boiler-room floor) to insure the 
air getting directly to the furnaoos. 

Ventilators should be so arranged as to sise and number that the air will 
be evenly distributed to the furnaces, and so designed that the sir TOlocities 
down the ventilators shall not exceed 1000 feet per minute. The total air 
should be calculated on the basis of the maximum rate of combustion, allow- 
ing not less than 300 cubic feet of free air per pound of coal or 260 cubic feet 
per pound of oil; and it should be assumed that all the air will enter through 
the ventilators, no dependence being placed on circulation through the 
fidley or through doors from the engine room to the fireroom. 

Howdea Heated Forced Draft is a combination of closed a^pit draft 
and a heater for heating the air for combustion. The heater consists of tubes 
located in the uptakes, through which the hot gases pass and around which 
the air is forced by blowers, and thence through ducts to the ashpits. A 
portion of the air is diverted to pass into the furnace around the fire-door 
opening; that is, through the eastings forming the door jambs and lintels. 

Howden heated forced draft when used is usually fitted to Scotch boilers, 
to which the design readily lends itself. (See Fig. 14.) The uptake where the 
heater is located is at the front of the boiler, from which ducts are easily carried 
to the ashpit and the latter being inside the boiler shell, is not liable to air and 
gas leakage (the main objection to ashpit draft). But most important of all, 
the high temperature of the waste gases leaving a Scotch boiler makes the 
air-heater very effective. Thus, Howden draft has been one of the most 
influential factors in keeping the Scotch boiler, with its excessive weight and 
high cost, within the range of fuel efficiencies required by modem engineering 
practice. 

Mr, Charles F. Bailey, Engineering Director of the Newport News Ship- 
building and Dry Dock Company, states in this connection: 

"The proportions of forced-draft air heaters may be expressed in the 
following ratios: 

Air heatiiig surface 



Main boiler heating surface 

Air heating surface 
Main boiler grate area ' 



0.26 to 0.31. 
10 to 12. 



Area through h eater t ubes no* in 
Area through boiler tubes 

Area through heater tubes « .„ . « ,«. 

». « 0.15 to 0.19. 

Grate area 

"We use tubes 3-inch outside diameter, No. 12 B.W.G. thick almost ex- 
clusively. The tubes are placed vertically and are usually about 48 inches 
long, the variation being not more than about 6 inches in either direction. 

"The heaters usually raise the temperature of the air about 150 deg. to 
175 deg., the temperature of the air as supplied to the furnace seldom exceed- 
ing 250 deg. 

"The ratio of the air supplied above the grate to the total air supplied 
varies considorably, but is from 0.15 to 0.2 in our best practice. More care-> 
ful consideration of this feature than is usually given might be worth while.** 

The data in Tables 1 and 2 on actual installations of Howden heaters 
are given by Mr. Robert Warriner^-Chief Engineer, Bethlehem Shipbuilding 
Corporation. 



GSNBBAL DBSlaS—DRAFT 






l^i'l 2:3 ^2 is?!!!? Is'^'Sjj"? ^ 















Hi 






llllllll 



352 



MARINE BOILERS 



Table 2. Air Velocities In Howden Heater Byetein 




■^^^^r^ 



fc^- 



Fio. 16. — ^Air Duets for Howden Heater. 



I.H.P. 2600, 

Oil per I.H.P. - 1.00 lb. per hr. 

Cu. ft. o£ air per lb. of oil i« 310 at 60 deg. F. 

r^ /* * •- -^ • 8600 X 1.00 X 310. 
Cu. ft. of air required per mia. ■- • 



Temp, of engine room, 96 deg. F. 
Temp, of air in duota. 100 deg. F. 
Temp, of air in heater, 2fiO deg. F. 



60 
Assumed. 



- 13,420 



Location 


Sue 


Area, 
sq.ft. 


Approx. 
temp^ 
deg. F. 


Cu. ft. 
per min. 


Velocity, 

ft. per 

min. 


A 


33* X43H' 
16J4''X43H'' 
16^'X43?** 
42* X33' 
12'-9»X2'-10H' 
2-'Xl3'X34W' 


9.94 
4.97 
4.97 
9.62 

25.55net 
6.27 


100 
100 
100 
100 
250 
250 


14.450 
7,225 
7,225 
4.817 
6.110 
6.110 


1.453 


B 


1.453 


C 


1,453 


Entrance to heaters 


501 


Heater space 


239 


Bxit from heaters 


974 







Sllie 6 BftTet Forced Draft is an application of induced draft in com- 
bination with heaters in the uptakes for heating the air for combustion. In 
this case the fans handle the waste gases, partially cooled by the air heater. 
(See Fig. 16.) 

A combination of dosed fireroom forced draft with air heaters has also been patented, 
but has found little application in practice for the reason that the best tjrpes of water^ 
tube boilers, which are the types employed at high capacity under doeed-fireroom con- 
ditions, hare such high heat absorbing qualities that the uptake temperatures are low* 
and thus yery large air heaters are required to obtain a fair degree of air heating, and 
even then the financial return due to the saving of waste heat is insufficient to pay a 
satisfactory return on first cost and upkeep expense. (See Tests, Cincinnati Boiler, p. 605.) 

8. Steam Pressure, Bflect on Design. In the large majority of cases 
the workinf pressure required at the engine fixes the boiler pressure, due 
allowance being made for frictional drop in steam lines including loss throu^ 
bends and fittings. With steam velocities of 5000 to 8000 feet per minute, 
this pressure drop will vary from 5 to 15 lbs. in the smaller installations with 
short piping connections, and from 20 to 25 lbs. in larger powered and 
highly forced equipment consisting of a multiplicity of boUer units in several 
compartments. If superheaters are fitted, an additional drop of a few 
pounds pressure must be allowed for. 



GENERAL DBSIGN — HTBAJU PRRfiSfi 



ipusB tuTe bMD uooMiIuUy iiiqployDd hf op«rRtiti« nub eosiiica throucb reducu 
v*lTea.the boilerpRHiuebciDfcouidenbl]' highartlun neouury Co averoomB ardiniii 
[rKtion in pipca, Thii rcaulU in  amkll nmouDt o[ luprthfat dot to nir»-dnwinc, u 
pTovJdva the wiuiroleDt at a nacrroir at ateam to mwt fluctuating losdfl. 




' Tha pteBnirea for which wftt«r-tub« boUert may be nonstnicted without 
departins (rom good practice are very high. W&r vessels frequently are 
fitted with the better type of this eeDsrator carrying more than 300 lbs., 
while in epedal caaea, 600 lbs. has been employed. One thousand pounds 
would not require any insurmountable modificatioDS in dniKn. Scoteh 
boDan, on the other hand, reach the hmit of proper ronstruction at about 
300 lbs. Above that either the plates become enormonnly thick for boiler 
work or the diameter of the shell must be greaUy reduced; and weights CHlready 
ueaaaive) become prohibitive. Advanced deaiEQers have indeed called 



364 MARINE BOILERS 

for Scotch boilers to oany 235 and even 260 lbs. ; but this inereaee in steam 
pressuret has brought with it not only unjustifiable wei^ts, but excessive 
cost of maintenance. 

4. Steam Output, llE^ot on D#sign. The boilers are required to 
furnish the necessary steam* to operate the propelling and auxiliary machinery 
at full capacity. "Horsepower." "indicated horsepower*' or "shaft horse- 
power" are the properly accepted terms for defining the capacity of the 
engine. They should not be used in connection with the boiler except as a 
basis for calculating the required steam output. The only proper msMiuro 
of this in En^ish units is the number of pounds of wator (aTotrdupoli) 
per hour which muit be eTaporatod to produce the dteam to operate the 
machinery, at the actual working pressure and from the actual feed tempera- 
ture. The term "honepower" at applied to boilen it, in faet, a 
mitnomor, for the boiler cannot produce horsepower or power of any kind 
unless it explodes. 

In land praotioe, the term ** boiler-horeepower" is aooepted and speeifieally defined 
by Bngineerinc Societies, so that a term looeely used in early days now signifies the defi- 
nite amount of heat imparted to the steam in evaporating an equivalent of 34H lbs. of 
water per hour ** from and at 212 deg. F." Stationary boUer manufacturers hove 
further aooustomed the land engineering fraternity to consider 10 sq. ft. of heating sm^ 
face in a bculer as being equal to one horsepower. They labor along with these ideas, 
and disooas this and that ** percentage of rating," etc., in a strenuous endeavor to keep 
pace with the times. Marine engineers should avoid this archaic anomaly. The boiler 
makes the steam to run the engine, and the engine, when it runs, makes the power, and 
the relative amount of power actually developed with the steam, depends entirely upon 
the efficiency of the engine. Furthermore, as noted above, heating surface will not make 
steam except as it is aooompanied by a furnace capable of burning the fuel. 

In estimating the steam required per hour as based on the horsepower of the 
main engines, it must be remembered that not only power developed, but 
siee, type and special features of design, working pressure, vacuum and 
whether saturated or superheated steam is used, also the type, number and 
arrangement of auxiliaries all materially affect the " water rate;" t.e., the 
steam consumption expressed in pounds of water to be evaporated per hour 
per horsepower. Thus, While the term "horsepower** as applied to boilers is 
to be avoided, the horsepower of the propelling machinery forms the basis 
for estimating the required steam output, and from this determining the 
proper sise of boiler. 

Rough rules for fixing the limits of grate and heating surface directly from 
the horsepower of the main engines are sometimes used. These must always 
be qualified by conditions and no two authorities are likely to agree exactly 
on the residts. Rough estimates of this kind should always be checked by 
more accurate data. Table 3 represents the views of five different 
authorities, whose rules have been compared and the maximum and minimum 
figures set down. They show the range which these rough estimates may 
take in the hands of various practical engineers. The difference in funnel 
height accounts in part for the variation, but the resulte emphasize the need of 
closer calculations. It may be noted that the minimum estimates for heating 
surface per horsepower for forced draft are less than for natural draft. This 
represents Scotch boiler practice, where the maximum amount of heating 
surface compared to grate surface which can be provided is limited and where 
the use of the Howden heater compensates to some extent for the loss in 
efficiency as the boiler is forced. If, however, the design of the boUer permits, 
it is advisable to keep the heating surface practically the same for both 
forced and natural draft, as obviously, the steam requirements are about 
identical in both cases. 



GENERAL DBSION—3TBAM OUTPUT 



355 



Tmblo S. Rough Bules for Gr&to mad HoatliMT Surface 

Based on Horsepower of Main Engines 



Type of vessel 



Propelling 
maebinefy 



Height 

funnel 

above 

«rate, 

feet 



Kind of 
fuel 



IGnd of 
draft 



HP. 

per 

sq. ft. of 

grate 



Sq. ft. of 
heating 
surface 

per H.P. 



Tug boat. 
Tu« boat. 
Tug boat. 
Tugboat. 



Bmall cargo vessel . . . 
Bmall cargo v e ss e l. . . 
Rmall cargo vessel. . . 
Small cargo vessel. . . 



T^erge 
large 
large 
Large 
lATge 



cargo 
cargo 
cargo 
cargo 
cargo 
cargo 



vessel, 
vessel, 
vessel. 

▼ CflOGl • 

vessel. 



Tknker 



Tanker 
cargo 

Tanker 
cargo 

Tanker 
cargo 



^r large 

vessel. . 
or large 

vesseL . 
or large 

veMel. , 
or large 

vesseT . 



Compound eng. 
Compound eng. 
Triple exp. eng. 
Triple exp. eng. 



30-60 

ao>5o 

30-50 
30-60 



Triple exp. eng. 1 50-75 
Triple ezp. eng.; 50-76 
Geared turbine 60-76 
Geared turbine 60-76 



Anth. 
coal 



Natural 
Forced 
Natural 
Forced 



Bit. coal 
Bit. coal 
Bit. coal 



Natural 

Forced 

Natural 



Bit. coal; Forced 



Triple exp. eng.,flO-90 
Triple exp. eng. '60^90 
Quad. exp. eng. '60-90 
Quad. exp. eng. 60-00 
Geared turbine '60-00 
Geared turbine 60-90 



Bit. coali 
Bit. eoall 
Bit. coal' 
Bit. ooal' 
Bit. ooal 
Bit. ooal 



Natural 

Forced 

Natural 

Foroed 

Natural 

Foroed 



5-^ 
7-10 
6-10 
9-14 



8-10 
1^14 
ia-12 
14-16 



9-11 
13-14.5 
10-12 
14-16 
10-12 
14-16 



8.76—6.0 

3.60—4.6 

3.76—5.0 

3.0—4.0 



3.5—4.0 
3.0—4.0 
3.0—3.75 
2.6—3.3 



FiuBt passenger veeeel. 

 Fwt paaeenger vessel. 

Fast passenger vessel. 

Ftet passenger vessel . 



Battleship. 
Battleship. 



Triple ezp. eng. 
Triple exp. eng. 
Geared turbine 
Geared turbine 



60-00 
60-90 
60-90 
60-90 



Geared turbine 170-120 
Geared turbine 70-120 



Geared turbine 
Geared turbine 



70-120 
70-120 



Direct turbine 
Geared turbine 



Destroyer Direct turbine 

Destroyer Geared turbine 



80-90 
80-90 



40-46 
40-46 



Oil 


Natural 


Oil 


Forced 


Oil 


Natural 


Oil 


Forced 


Bit. coal 
Bit. coal 
Oil 
Oil 


Natural 
Forced 
Natural 
Forced 


Oil 
Oil 


Forced 
Forced 


OU 
Oil 


Foroed 
Forced 



.00—4.0 
,76—3.8 
75—3.75 
,60—3.76 
,00—3.75 
60—3.65 



3.00—3.75 
2.65—3.6 
2.80—3.5 
2.40—3.5 



12-14 
14-16 



3.00— S. 75 
2.50—3.60 
2.80-3.60 
2.40—3.50 



1.6—2.0 
1.0—2.0 



1.1 
1.0 



T»bl« 4. Steam Constiinption for all FurpoMS 



T31W of engine 


Indicated 
shaft horse power 


Steam consump- 
tion per I. H.P. or 
aH.P. AH pur- 
poses 


Plus 20 per cen», 
approximately 


Compound engines 


400-800 
1300-2000 
3Q0O-5000 


20 


24 


Triple engines 


80 


Trifde engines 


19 


Quadruple. 

Geared turbine 

Geared turbine ' 


3000-5000 

1500-2500 


18 
17 
16 







In €»timating the steam required per hour as based on the horsepower of 
the main engines, it is customary to include the steam used by the auxiliaries, 
etc.; in other words, to use a water rate, based on the maximum horsepower 
of the propelling engines, which will include the steam required for all pur- 
poses. The water rate or steam consumption of the machinery of merchant 
vessels in Table 4 is given by Mr, Charles F, Bailey, who states that 



354 MARINE BOILERS 

for Scotch boilers to carry 235 and even 260 lbs. ; but this inereaae in steam 
pressures has brought with it not only unjustifiable weights, but excessive 
cost of maintenance. 

4. Steam Output, Kfl«ot on Design. The boilers are required to 
furnish the necessary steam* to operate the propelling and auxiliary machinery 
at full capacity. "Horsepower," "indicated horsepower" or "shaft horse- 
power" are the properly accepted terms for defining the capacity of the 
engine. They should not be used in connection with the boiler except as a 
basis for calculating the required steam output. The only proper moasuro 
of this in Eni^ish units is the number of pound! of water (aTolrdupoU) 
per hour which must bo OTaporated to produce the steam to operate liie 
machinery, at the actual working pressure and from the actual feed tempera- 
ture. The torm "honopower" as applied to boilerg it, in fact, a 
miinomor, for the boiler cannot produce horsepower or power of any kind 
unless it explodes. 

In land praotioe, the term " boiler-horsepower" is sooepted and tpecifioally defined 
by Engineering Societies, so that a term loosely used In early days now signifies the defi- 
nite amount of heat imparted to the steam in evaporating an equivalent of 34H Iba. of 
water per hour *' from and at 212 deg. F." Stationary boiler manufacturers have 
further acoustomed the land engineering fraternity to consider 10 sq. ft. of heating ssr- 
faoe in a boUer as being equal to one horsepower. They labor along with these idesa, 
and discuss this and that " percentage of rating,'* etc., in a strenuous endeavor to keep 
pace with the times. Marine engineers should avoid this archaic anomaly. The bo3c»' 
makes the steam to run the engine, and the engine, when it runs, makes the power, and 
the relative amount of powo* actually developed with the steam, depends entirely upon 
the efficiency of the engine. Furthermore, as noted above, heating surface will not make 
steam except as it is accompanied by a furnace capable of burning the fuel. 

In estimating the steam required per hour as based on the horsepower of the 
main engines, it must be remembered that not only power developed^ but 
sise, type and special features of design, working pressure, vacuum and 
whether saturated or superheated steam is used, also the type, number and 
arrangement of auxiliaries all materially affect the " water rate;" t.e., the 
steam consumption expressed in pounds of water to be evaporated per hour 
per horsepower. Thus, While the term "horsepower" as applied to boilers is 
to be avoided, the horsepower of the propelling machineiy forms the basis 
for estimating the required steam output, and from this determining the 
proper size of boiler. 

Rough rules for fixing the limits of grate and heating surface directly from 
the horsepower of the main engines are sometimes used. These must always 
be qualified by conditions and no two authorities are likely to agree exactly 
on the results. Rough estimates of this kind should always be checked by- 
more accurate data. Table 3 represents the views of five different 
authorities, whose rules have been compared and the maximum and minimuzQ 
figures set down. They show the range which these rough estimates may 
take in the hands of various practical engineers. The difference in funnel 
height accounts in part for the variation, but the resulte emphasize the need of 
closer calculations. It may be noted that the minimum estimates for heatinjg 
surface per horsepower for forced draft are less than for natural draft. This 
represents Scotch boiler practice, where the maximum amount of heating 
surface compared to grate surface which can be pro\'ided is limited and where 
the use of the Howden heater compensates to some extent for the loss in 
efficiency as the boiler is forced. If, however, the design of the boiler permits, 
it is advisable to keep the heating surface practically the same for both 
forced and natural draft, as obviously, the steam requirements are about 
identical in both cases. 



GENERAL DESIGN— STEAM OUTPUT 



355 



Tttble S. Bough Boles for Orate and Heating Surface 

Based on Horsepower of Main Engines 



Tjrpe of veaeel 


Propelling 
maeninery 


Height 

funnel 

above 

«rate, 

feet 


Kind of 
fuel 


IIP. 
rond of i>er 
draft jsq. ft. of 
1 grate 

1 


1 

8q. ft. of 
heating 
surface 
per H.P. 


Tag boat 


Compound eng. 
Compound eng. 
Triplie exp. eng. 
Triple esp. eng. 


30-50 
30-50 
30-50 
30-50 


Anth. 
coal 


Natural 
Forced 
Natural 
Forced 


5-8 
7-10 
6-10 
9-14 


8.75—6.0 


Tug boat 


3.50—4.5 


Tugboat 


3.75—5.0 


Tugboat 


3.0— 4.0 






Small cargo vessel 

Hoiall cargo vessel 

Hmall cargo vessel 

Small cargo vessel. . . . 


Triple exp. eng. 
IViple exp. eng. 
Geared turbine 
Oeared turbine 


50-75 
50-76 
50-75 
50-75 


Bit. coal Natural 
Bit. ooal Forced 
Bit. ooal Natural 
Bit. ooali Forced 


8-10 
1^14 
10-12 
14-16 


3.5—4.0 
3.O-4.0 
3.0—3.75 
2.6—3.3 


lisrge cargo vessel 

Large cargo vessel 

Urge cargo vessel 

large cargo vessel. . . . 
Ji«ig© cargo vessel. . . . 
Urge cargo vessel. . . . 


Triple exp. eng. 
Triple exp. eng. 
Quad. exp. eng. 
Quad. exp. eng. 
Geared turbine 
Geared turbine 


60-90 
60^90 
60-90 
60-90 
60-90 
60-90 


Hit. coal Natural 
Bit. coal! Forced 
Bit. coal' Natural 
Bit. ooal Forced 
Bit. ooal Natural 
Bit. coal Forced 

1 


9-11 
13-14.5 
10-12 
14-16 
10-12 
14-16 


3.00—4.0 

2.75—3.8 

2.75—3.75 

2.50—3.75 

3.00—3.76 

2.50—3.65 


Tanker or large 

eargo vessel 

Tknker or large 

eargo vesseT 

Tanker or large 

eargo vessel 

Tanker or large 

eargo vessef 


Triple exp. eng. 
Triple exp. eng. 
Geared turbine 
Geared turbine 


60-90 
60-90 
60-90 
60-90 


Oil 
Oil 

oa 

Oil 


Natural 
Forced 
Natural 
Forced 




3.0O— 3.75 
2.65— «. 6 
2.80—3.5 
2.40—3.5 


Fast passenger vessel. 
Fast passenger vessel. 
Fsst passenger vessel. 
f^tt passenger vessel. 


Geared turbine 
Geared turbine 
Geared turbine 
Geared turbine 


70-120 
70-120 
70-120 
70-120 


Bit. ooal 
Bit. coal 
Oil 

oa 


Natural 
Forced 
Natural 
Forced 


12-14 
14-16 


3.00—5.75 
2.50—3.60 
2.80-3.50 
2.40—^.60 


Battlahip 


IMrect turbine 


AA-flO 


Ofl 
Oil 


Forced 
Forced 




1.5—2.0 


Battleship 


Geared turbine 180-90 

1 


1.0—2.0 


Destroyer 

Bartroyer j 




Direct turbine 40-45 
Geared turbine 40-45 


OU 
Oil 


Forced 
Forced 




1.1 
1.0 



Table 4. Steam OonsUmption for all Purposes 



Type of engine 


Indicated 
shaft horse power 


Steam consump- 
tion per I. H.P. or 
8. H.P. All pur- 
poses 


Plus 20 per oen*, 
approximately 


Compound engines 

Tripte engines 

I^ipls engiBes 


400-800 

iaoo-2000 

3000-5000 


20 


24 
20 
19 


G^d turbine . *.!!!!.'!!!!.' 
Geared turbine 


3000-SOOO 

1 500-2500 
30004000 


18 
17 
16 



In eetimating the steam required per hour as based on the horsepower of 
the main engines, it is customary to include the steam used by the auxiliaries, 
etc.; in other words, to use a water rate, based on the maximum horsepower 
of the propelling engines, which will include the steam required for all pur- 
posee. The water rate or steam consumption of the machinery of merchant 
yesaels in Table 4 is given by Mr, Charles F. Bailey, who states that 



340 UARIUS 

tbe bdl«r li *dded to that nl tha friction a( ths (■«■ lOtoriiv th* toncM uid tht po- 
centaaa ol okmii(« witli tiutIbi fir* bed ooDdiiHiu ia titBtly rBdaoBd. While tbt frio- 
tion of tb? B**H tJuou^ m boilar HTttinc variea Bomswhat with thv rate of fordbg. 
dai^n and type of thfi boiler uid the propordon af hcaLitm surface to crate lUTfue, 
theae chaoiH an ]e« importaot thao the chaaged nsiitanoe of tbc Gre bed and ita 
erratic effect CD tbe draft £age- For tboe reHaooa, the writer believea that it is morf 
praotical to baae oaloulatiDUa on draft dilTcreDee betwneo the -uplake and the firerODin 
ratber than between the finroom and the fumaoe. The fireroom pneaure ia uacd Inataid 
of the aahpit preaaun. aa at bifb ntea of f oreinc tha« ia a ilicht drop in pnaaure u the 
paaaac* of the ur tbrou(h the aah-doora. 

Tha (ollowiDg reaulta were obtained in % large nuiBb«r of twt>, trial 
trip*, eto., with Baboock t Wilooz Moiine Boilen, with Bemi-bitumiuouB 
mine-run ooaJ, h&nd fired: 









Draft iwuired. 

Diffeteneebetween 
b^er^»p«r^ 


Coal bnnml par 

jrate per hour, 
pounda 




n.i 

M.O 


8il! 

■.It 

a'.a 


17 .5 

1! 


( 


1 



Cool per Squart Foot- of '6raH per Hgur in Psunda 
Fmj. 12. 

These figurM are represented graphically in Fig. 12. It ia to be noted that 
this chart may be used for forced draft as well as natural draft, as the ordinat«B I 
indicate the algebraic difference between draft preasures in the uptak* at 
the outlet from the boiler and the Sreroom, 



OBNBRAL DEaiON^DRAPT 847 

WfUtmA 4nit tor inoreMiBg the r«te of oombmtioii may be variously ap* 
)»Iied. In the GlOMd-Mhpit arrangemeoi, the Uowera foroe air under prea^ 
rare to th